chore: bump version 0.15.0 → 0.16.0 (p10-1d C + C++ AST chunkers)

Minor bump — additive new chunker_versions code-c-ast-v1 + code-cpp-ast-v1
+ new routing langs c / cpp + new tree-sitter-c / tree-sitter-cpp workspace
deps. P10 Tier 1 chunker family complete. No DB migration, no wire schema
major bump.

Also lands the missing p10-3 try_skip_unchanged fallback-aware fix (Option
B1 — 7th param) that PR #155 was supposed to ship but never made it to main
(implementer reported commit SHA 2a39513 that didn't exist in the merged
branch). Same commit extends tier3_fallback_cv to include c/cpp.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Cargo.toml

@@ -31,7 +31,7 @@ edition       = "2024"
 rust-version  = "1.85"
 license       = "MIT OR Apache-2.0"
 repository    = "https://github.com/altair823/kebab"
-version       = "0.15.0"
+version       = "0.16.0"
 
 [workspace.dependencies]
 anyhow       = "1"