feat: add sources --format, optimize gateway commands, improve test coverage

Features:
- Add --format json option to sources command per RFC-0002:C-SOURCES

Performance:
- outline: use pre-built headings index when available (O(1) vs O(n) file scan)
- sources: optimize mark_last_entries from O(n²) to O(n)

Tests:
- Add unit tests for index.rs (76% → 96%) and sync.rs (70% → 86%)
- Add unit tests for logging.rs (78% → 93%)
- Add integration tests for logging behavior
- Add outline tests for both built (index) and unbuilt (fallback) paths
- Add sources integration tests for all options

Docs:
- Update RFC-0002 with --format option for sources
- Update README with sources --format json example
- Update CHANGELOG with new features and performance improvements
- Fix outdated lint rule numbers in validating.md workflow
- Add tree output example to testing.md workflow

Overall test coverage: 87.93% → 88.48%

Author: lucifer1004

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "skillc"
-version = "0.1.1"
+version = "0.2.0"
 edition = "2024"
 license = "MIT OR Apache-2.0"
 description = "A development kit for Agent Skills - the open format for extending AI agent capabilities"

Cargo.toml

@@ -105,6 +105,7 @@ skc show my-skill --section "API" --max-lines 50  # Truncate output
 skc open my-skill SKILL.md --max-lines 100        # Read first 100 lines
 skc search my-skill "borrow checker"
 skc sources my-skill --pattern "*.md"
+skc sources my-skill --format json          # JSON output
 
 # Analytics
 skc stats my-skill --group-by sections

README.md

@@ -1,9 +1,9 @@
 <!-- GENERATED: do not edit. Source: RFC-0002 -->
-<!-- SIGNATURE: sha256:672a3198ebf3468d08e85e0d60892add77b7e414be7b3e4ebe4b504f17450adc -->
+<!-- SIGNATURE: sha256:4d3ec959504d040daf017ecc16258ba108dacad6458122eb5a4060efdfda8dd8 -->
 
 # RFC-0002: Gateway Protocol
 
-> **Version:** 0.1.0 | **Status:** normative | **Phase:** test
+> **Version:** 0.2.1 | **Status:** normative | **Phase:** test
 
 ---
 
@@ -210,6 +210,7 @@ The sources command MUST list all files in the skill's source directory in a tre
 | `--dir <path>` | Scope listing to a subdirectory |
 | `--limit <n>` | Maximum entries to display (default: 100) |
 | `--pattern <glob>` | Filter files by glob pattern (e.g., `*.md`) |
+| `--format <fmt>` | Output format: `text` (default) or `json` |
 
 **Output format:**
 
@@ -251,10 +252,14 @@ The command MUST reject any `--dir` path that would resolve outside the skill so
 
 ## Changelog
 
-### v0.1.0 (2026-01-30)
+### v0.2.1 (2026-01-31)
 
-Initial release
+Add missing --format support for 
+
+### v0.2.0 (2026-01-31)
 
-#### Added
+C-SHOW updated with em-dash stripping and suggestions
 
-- C-SHOW updated with em-dash stripping and suggestions
+### v0.1.0 (2026-01-30)
+
+Initial release

docs/rfc/RFC-0002.md

@@ -1,9 +1,9 @@
 <!-- GENERATED: do not edit. Source: RFC-0004 -->
-<!-- SIGNATURE: sha256:975e35b3688109154ff5d2ee3d885a3ee23bbc204a953a0c53c0938daed4892d -->
+<!-- SIGNATURE: sha256:72a6a5ccaa9dfbddd02590f892babad2362bdae67c5fd2210f7fafd6218d2d56 -->
 
 # RFC-0004: Search Protocol
 
-> **Version:** 0.1.0 | **Status:** normative | **Phase:** test
+> **Version:** 0.2.0 | **Status:** normative | **Phase:** test
 
 ---
 
@@ -380,10 +380,10 @@ An index is corrupt if the database cannot be opened, `index_meta` table is miss
 
 ## Changelog
 
-### v0.1.0 (2026-01-30)
+### v0.2.0 (2026-01-31)
 
-Initial release
+C-INDEX updated with headings table, schema version bumped to 2
 
-#### Added
+### v0.1.0 (2026-01-30)
 
-- C-INDEX updated with headings table, schema version bumped to 2
+Initial release

docs/rfc/RFC-0004.md

@@ -61,12 +61,21 @@ Opens a specific file from the skill. Use this for non-markdown files or when yo
 skc sources my-skill
 ```
 
-Lists all files in the skill:
+Lists all files in the skill as a tree:
 
 ```
-SKILL.md
-examples/usage.md
-reference/api.md
+my-skill/
+├── SKILL.md
+├── examples/
+│   └── usage.md
+└── reference/
+    └── api.md
+```
+
+Use `--format json` for machine-readable output:
+
+```bash
+skc sources my-skill --format json
 ```
 
 ### Search content

docs/workflows/testing.md

@@ -12,35 +12,42 @@ This checks your skill against quality rules and reports any issues.
 
 ## What lint checks
 
-### Structure rules (SKL0xx)
+See [RFC-0008:C-REGISTRY](../rfc/RFC-0008.md#rfc-0008c-registry) for the full rule specification.
+
+### Meta rules (SKL0xx)
 
 - **SKL001**: Skip compiled skills (internal)
-- **SKL002**: `SKILL.md` must exist at skill root
-- **SKL003**: No empty directories
-
-### File rules (SKL1xx)
-
-- **SKL101**: Frontmatter must be valid YAML
-- **SKL102**: `name` field required in frontmatter
-- **SKL103**: `description` field required in frontmatter
-- **SKL104**: `name` must match directory name
-- **SKL105**: `description` should be 10-200 characters
-- **SKL106**: Title heading should match skill name
-- **SKL107**: Skill should have activation triggers
-- **SKL108**: `description` shouldn't start with "A skill..."
+
+### Frontmatter rules (SKL1xx)
+
+- **SKL100**: Frontmatter must be valid YAML
+- **SKL101**: `name` field required
+- **SKL102**: `name` format (lowercase, hyphens, digits only)
+- **SKL103**: `name` length (1-64 chars)
+- **SKL104**: `name` should match directory name
+- **SKL105**: `description` field required
+- **SKL106**: `description` must be non-empty
+- **SKL107**: `description` length (10-200 chars recommended)
+- **SKL108**: Include activation triggers
 - **SKL109**: Only known frontmatter fields allowed
 
-### Markdown rules (SKL2xx)
+### Structure rules (SKL2xx)
 
-- **SKL201**: Headings should use ATX style (`#`)
-- **SKL202**: Single H1 per file
-- **SKL203**: No skipped heading levels
-- **SKL204**: No trailing punctuation in headings
+- **SKL201**: SKILL.md size warning (>500 lines)
+- **SKL202**: Missing H1 heading
+- **SKL203**: H1 should match skill name
+- **SKL204**: First heading should be H1
+- **SKL205**: No skipped heading levels
 
 ### Link rules (SKL3xx)
 
 - **SKL301**: Internal links must resolve
 - **SKL302**: Anchor links must resolve
+- **SKL303**: Links must not escape skill root
+
+### File rules (SKL4xx)
+
+- **SKL401**: No orphan files (files not linked from SKILL.md)
 
 ## Output formats
 

docs/workflows/validating.md

@@ -49,5 +49,5 @@
       "notes": "Initial release"
     }
   ],
-  "signature": "b1fea06be63537da56748e580c5cd3c6fe983b2ff0f8428578921fe8f390f6f8"
+  "signature": "94b3db4a23d6c62af6a620d43a06f82f367205019ace5b25764890d397886fb7"
 }

gov/rfc/RFC-0001/rfc.json

@@ -3,6 +3,6 @@
   "title": "Sources Command",
   "kind": "normative",
   "status": "active",
-  "text": "**Syntax:** `skc sources <skill> [options]`\n\nThe sources command MUST list all files in the skill's source directory in a tree-style format.\n\n**Options:**\n\n| Option | Description |\n|--------|-------------|\n| `--depth <n>` | Maximum tree depth to display (default: unlimited) |\n| `--dir <path>` | Scope listing to a subdirectory |\n| `--limit <n>` | Maximum entries to display (default: 100) |\n| `--pattern <glob>` | Filter files by glob pattern (e.g., `*.md`) |\n\n**Output format:**\n\nThe command MUST output a tree-style directory listing:\n- Files are listed with their relative paths\n- Directories that are not expanded MUST show a file count suffix: `dirname/ (N files)`\n- When `--limit` is exceeded, output MUST end with a truncation indicator: `... (N more)`\n\n**Ordering:**\nEntries MUST be sorted lexicographically by relative path (bytewise ASCII order), with directories listed before files at each level.\n\n**Example output:**\n\n```\n$ skc sources cuda --depth 2\ncuda/\n├── SKILL.md\n├── references/\n│   ├── compilation.md\n│   ├── cuda-driver-docs/ (156 files)\n│   ├── cuda-runtime-docs/ (89 files)\n│   ├── debugging-tools.md\n│   └── ... (8 more)\n```\n\n**Scoped listing:**\n\nWhen `--dir` is provided, the command MUST:\n- Validate that the path exists within the skill root\n- Display the subtree rooted at that directory\n- Apply `--depth` relative to the specified directory\n\n**Path safety:**\nThe command MUST reject any `--dir` path that would resolve outside the skill source directory after canonicalization. See [[RFC-0005:C-CODES]] for error E012.",
+  "text": "**Syntax:** `skc sources <skill> [options]`\n\nThe sources command MUST list all files in the skill's source directory in a tree-style format.\n\n**Options:**\n\n| Option | Description |\n|--------|-------------|\n| `--depth <n>` | Maximum tree depth to display (default: unlimited) |\n| `--dir <path>` | Scope listing to a subdirectory |\n| `--limit <n>` | Maximum entries to display (default: 100) |\n| `--pattern <glob>` | Filter files by glob pattern (e.g., `*.md`) |\n| `--format <fmt>` | Output format: `text` (default) or `json` |\n\n**Output format:**\n\nThe command MUST output a tree-style directory listing:\n- Files are listed with their relative paths\n- Directories that are not expanded MUST show a file count suffix: `dirname/ (N files)`\n- When `--limit` is exceeded, output MUST end with a truncation indicator: `... (N more)`\n\n**Ordering:**\nEntries MUST be sorted lexicographically by relative path (bytewise ASCII order), with directories listed before files at each level.\n\n**Example output:**\n\n```\n$ skc sources cuda --depth 2\ncuda/\n├── SKILL.md\n├── references/\n│   ├── compilation.md\n│   ├── cuda-driver-docs/ (156 files)\n│   ├── cuda-runtime-docs/ (89 files)\n│   ├── debugging-tools.md\n│   └── ... (8 more)\n```\n\n**Scoped listing:**\n\nWhen `--dir` is provided, the command MUST:\n- Validate that the path exists within the skill root\n- Display the subtree rooted at that directory\n- Apply `--depth` relative to the specified directory\n\n**Path safety:**\nThe command MUST reject any `--dir` path that would resolve outside the skill source directory after canonicalization. See [[RFC-0005:C-CODES]] for error E012.",
   "since": "0.1.0"
 }

gov/rfc/RFC-0002/clauses/C-SOURCES.json

@@ -1,12 +1,12 @@
 {
   "rfc_id": "RFC-0002",
   "title": "Gateway Protocol",
-  "version": "0.1.0",
+  "version": "0.2.1",
   "status": "normative",
   "phase": "test",
   "owners": ["@govctl-org"],
   "created": "2026-01-26",
-  "updated": "2026-01-30",
+  "updated": "2026-01-31",
   "sections": [
     {
       "title": "Summary",
@@ -24,11 +24,21 @@
     }
   ],
   "changelog": [
+    {
+      "version": "0.2.1",
+      "date": "2026-01-31",
+      "notes": "Add missing --format support for "
+    },
+    {
+      "version": "0.2.0",
+      "date": "2026-01-31",
+      "notes": "C-SHOW updated with em-dash stripping and suggestions"
+    },
     {
       "version": "0.1.0",
       "date": "2026-01-30",
-      "notes": "Initial release",
-      "added": ["C-SHOW updated with em-dash stripping and suggestions"]
+      "notes": "Initial release"
     }
-  ]
+  ],
+  "signature": "4d3ec959504d040daf017ecc16258ba108dacad6458122eb5a4060efdfda8dd8"
 }