feat: TUI, MCP server, session manager & profiles rename (#23)

* feat: TUI, MCP server, session manager & profiles rename

- Interactive TUI with bubbletea: Projects/Profiles/Settings tabs,
  left-right split panels, project detail with git status
- MCP server over stdio with 6 tools (list_projects, add_project,
  remove_project, list_profiles, switch_profile, get_project_info)
- Session manager: launch Claude in separate terminal windows,
  multi-instance per project, PID tracking, configurable terminal
- JSON output mode via --json flag
- Rename "Configs" to "Profiles" throughout codebase with backward
  compatible JSON deserialization (old "configs" field auto-migrates)
- New Settings tab for Terminal, Default Behavior, Skip Permissions
- CI workflows updated to Go 1.24

Closes #21, closes #19, closes #16

* docs: update README for TUI, MCP, profiles & settings

Rewrite README to document new features: interactive TUI with three
tabs, MCP server tools, session manager, terminal configuration,
profiles rename, and settings tab. Update config format from
"configs" to "profiles" with backward compat note. Update Go
requirement to 1.24 and project structure.

* fix: prevent command injection in session launch and fix TUI race condition

- Sanitize session IDs to alphanumeric/underscore/hyphen/dot only
- Escape AppleScript strings to prevent injection via project names
- Validate shell env var names against POSIX pattern before export
- Fix TUI profile switch closure to not mutate shared config pointer

Author: ourines

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
     - name: Setup Go
       uses: actions/setup-go@v5
       with:
-        go-version: '1.21.x'
+        go-version: '1.24.x'
         cache: true
 
     - name: Install dependencies

.github/workflows/release.yml

@@ -45,7 +45,7 @@ jobs:
     - name: Setup Go
       uses: actions/setup-go@v5
       with:
-        go-version: '1.21.x'
+        go-version: '1.24.x'
         cache: false
 
     - name: Install dependencies