cid(advance): add language logos to README section headers

Add inline Simple Icons CDN logos to all 18 language headers
(9 Installation + 9 Quick Start). Consistent 20x20 sizing with
alt text for accessibility.

Author: CID Agent

.claude/context/handoff.md

@@ -1,37 +1,27 @@
-## 2026-03-08 — Review of: Add SHA512 checksums to vcpkg portfile
+## 2026-03-08 — Add language logos to README
 
-**Verdict:** PASS
+**Done:** Added inline `<img>` tags with Simple Icons CDN logos to all 18 language section headers
+in README.md (9 Installation + 9 Quick Start). Each header has consistent `width="20" height="20"`
+sizing and `alt` text for accessibility.
 
-**Summary:** The advance agent replaced `SKIP_SHA512` with per-platform SHA512 checksums in
-`packages/cpp/portfile.cmake`. All 5 checksums were independently verified by downloading the v0.2.0
-release tarballs and computing SHA512 sums — every hash matches. The change is minimal, correct, and
-within scope.
+**Files changed:**
 
-**Verification:**
-
-- [x] `SKIP_SHA512` removed from portfile — grep confirms absence
-- [x] `ISCC_SHA512` appears exactly 6 times (5 `set()` + 1 `SHA512` usage)
-- [x] `SHA512 "${ISCC_SHA512}"` pattern present in download call
-- [x] Each SHA512 hash is 128 lowercase hex characters — `grep -cP` returns 5
-- [x] CMake syntax valid — errors on vcpkg functions (expected), not on syntax
-- [x] All 15 pre-commit hooks pass (`mise run check`)
-- [x] All 5 checksums independently verified against actual downloaded tarballs
-- [x] `cargo clippy --workspace --all-targets -- -D warnings` clean
-
-**Issues found:**
+- `README.md`: Added `<img>` logo tags to 18 `###` headers using Simple Icons CDN URLs
 
-- (none) — clean implementation
-
-**Codex review:** No actionable findings. Codex confirmed the change is limited to replacing
-`SKIP_SHA512` with per-platform SHA512 pins and introduces no correctness or compatibility
-regressions.
-
-**Next:** The only remaining `normal`-priority issue is "Add programming language logos to README
-and docs." After that, only `low`-priority items remain (Swift/Kotlin bindings) and the CID loop
-should signal idle.
+**Verification:**
 
-**Notes:** The resolved vcpkg SHA512 issue has been deleted from issues.md. The advance handoff
-correctly noted that future releases will need SHA512 checksums updated — this is not automated yet
-(explicitly out of scope per next.md). The Conan recipe (`conanfile.py`) also lacks SHA512
-verification but no issue is filed for it. State.md line 135-136 still references the open issue —
-update-state will pick this up next cycle.
+- `grep -c '<img src=.*simpleicons.*width=' README.md` → 18 (pass)
+- `grep -c 'alt="' README.md` → 18 (pass)
+- `grep -cP '(rust|python|nodedotjs|openjdk|go/|ruby|dotnet|cplusplus|webassembly)' README.md` → 23
+    (≥18, pass — extra matches from code blocks and URLs)
+- `mise run format` → exits 0 (pass)
+- `mise run check` → all 15 hooks pass
+
+**Next:** All normal-priority issues are resolved. Only low-priority items remain (Swift/Kotlin
+bindings). The CID loop should signal idle or move to the docs site logo follow-up if desired.
+
+**Notes:** Used `CE412B` (Rust's classic orange-red) instead of `000000` (black) for the Rust logo
+color. Black is invisible on GitHub's dark mode background, making it genuinely unusable. The
+orange-red is the color most associated with Rust (ferris crab, original logo) and has sufficient
+contrast on both light and dark backgrounds. All other colors used as suggested in next.md. The
+`openjdk` slug was used for Java as recommended.

README.md

@@ -76,25 +76,25 @@ ecosystems who need fast, reliable content identification.
 
 ## Installation
 
-### Rust
+### <img src="https://cdn.simpleicons.org/rust/CE412B" width="20" height="20" alt="Rust"> Rust
 
 ```bash
 cargo add iscc-lib
 ```
 
-### Python
+### <img src="https://cdn.simpleicons.org/python/3776AB" width="20" height="20" alt="Python"> Python
 
 ```bash
 pip install iscc-lib
 ```
 
-### Node.js
+### <img src="https://cdn.simpleicons.org/nodedotjs/5FA04E" width="20" height="20" alt="Node.js"> Node.js
 
 ```bash
 npm install @iscc/lib
 ```
 
-### Java
+### <img src="https://cdn.simpleicons.org/openjdk/ED8B00" width="20" height="20" alt="Java"> Java
 
 ```xml
 <dependency>
@@ -106,39 +106,39 @@ npm install @iscc/lib
 
 The native library must be available on `java.library.path` at runtime.
 
-### Go
+### <img src="https://cdn.simpleicons.org/go/00ADD8" width="20" height="20" alt="Go"> Go
 
 ```bash
 go get github.com/iscc/iscc-lib/packages/go
 ```
 
-### Ruby
+### <img src="https://cdn.simpleicons.org/ruby/CC342D" width="20" height="20" alt="Ruby"> Ruby
 
 ```bash
 gem install iscc-lib
 ```
 
-### C# / .NET
+### <img src="https://cdn.simpleicons.org/dotnet/512BD4" width="20" height="20" alt="C# / .NET"> C# / .NET
 
 ```bash
 dotnet add package Iscc.Lib
 ```
 
-### C / C++
+### <img src="https://cdn.simpleicons.org/cplusplus/00599C" width="20" height="20" alt="C / C++"> C / C++
 
 Pre-built release tarballs are attached to each
 [GitHub Release](https://github.com/iscc/iscc-lib/releases). Download for your platform — includes
 shared library, static library, `iscc.h` header, and `iscc.hpp` C++ wrapper.
 
-### WASM
+### <img src="https://cdn.simpleicons.org/webassembly/654FF0" width="20" height="20" alt="WASM"> WASM
 
 ```bash
 npm install @iscc/wasm
 ```
 
 ## Quick Start
 
-### Rust
+### <img src="https://cdn.simpleicons.org/rust/CE412B" width="20" height="20" alt="Rust"> Rust
 
 ```rust
 use iscc_lib::gen_meta_code_v0;
@@ -147,7 +147,7 @@ let result = gen_meta_code_v0("ISCC Test Document!", None, None, 64).unwrap();
 println!("Meta-Code: {}", result.iscc);
 ```
 
-### Python
+### <img src="https://cdn.simpleicons.org/python/3776AB" width="20" height="20" alt="Python"> Python
 
 ```python
 import iscc_lib as ic
@@ -156,7 +156,7 @@ result = ic.gen_meta_code_v0("ISCC Test Document!")
 print(f"Meta-Code: {result['iscc']}")
 ```
 
-### Node.js
+### <img src="https://cdn.simpleicons.org/nodedotjs/5FA04E" width="20" height="20" alt="Node.js"> Node.js
 
 ```javascript
 const ic = require("@iscc/lib");
@@ -165,7 +165,7 @@ const result = ic.gen_meta_code_v0("ISCC Test Document!");
 console.log(`Meta-Code: ${result.iscc}`);
 ```
 
-### Java
+### <img src="https://cdn.simpleicons.org/openjdk/ED8B00" width="20" height="20" alt="Java"> Java
 
 ```java
 import io.iscc.iscc_lib.IsccLib;
@@ -174,7 +174,7 @@ String result = IsccLib.genMetaCodeV0("ISCC Test Document!", null, null, 64);
 System.out.println("Meta-Code: " + result);
 ```
 
-### Go
+### <img src="https://cdn.simpleicons.org/go/00ADD8" width="20" height="20" alt="Go"> Go
 
 ```go
 package main
@@ -195,7 +195,7 @@ func main() {
 }
 ```
 
-### Ruby
+### <img src="https://cdn.simpleicons.org/ruby/CC342D" width="20" height="20" alt="Ruby"> Ruby
 
 ```ruby
 require "iscc_lib"
@@ -204,7 +204,7 @@ result = IsccLib.gen_meta_code_v0("ISCC Test Document!")
 puts "Meta-Code: #{result.iscc}"
 ```
 
-### C# / .NET
+### <img src="https://cdn.simpleicons.org/dotnet/512BD4" width="20" height="20" alt="C# / .NET"> C# / .NET
 
 ```csharp
 using Iscc.Lib;
@@ -213,7 +213,7 @@ var result = IsccLib.GenMetaCodeV0("ISCC Test Document!");
 Console.WriteLine($"Meta-Code: {result.Iscc}");
 ```
 
-### C++
+### <img src="https://cdn.simpleicons.org/cplusplus/00599C" width="20" height="20" alt="C++"> C++
 
 ```cpp
 #include <iscc/iscc.hpp>
@@ -225,7 +225,7 @@ int main() {
 }
 ```
 
-### WASM
+### <img src="https://cdn.simpleicons.org/webassembly/654FF0" width="20" height="20" alt="WASM"> WASM
 
 ```javascript
 import {