feat(config): codegraph.json include to force gitignored first-party source into the index (#1063)

Adds an `include` list to the root `codegraph.json` that forces gitignored first-party source (second-VCS / SVN / Perforce dual-tracked repos) into the index — discovered directly off disk on the full index, incremental sync, and file-watching, on both git and non-git projects. Gitignore-style patterns, root-relative; explicit `exclude` still wins and built-in skips (node_modules, dist, .git) are never re-included. Complements `exclude` and `includeIgnored`.

Closes #1163.

Thanks @luoyxy for the contribution.

CHANGELOG.md

@@ -32,6 +32,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - Anonymous usage telemetry now counts how often the context hook injected context, offered a hint, or stayed silent — fixed counter names only; the prompt's content is never stored or sent. This makes the hook's accuracy measurable instead of guessed. The counters record what actually happened, not what was attempted: a lookup that errors or comes back empty counts as a distinct silent outcome, never as delivered context (#1143, thanks @inth3shadows).
 - Metal shader files (`.metal`) are now indexed. Metal Shading Language is close enough to C++ that vertex/fragment/kernel functions, structs, type aliases, and the calls between them all land in the graph — so shader pipelines in Apple-platform projects show up in impact analysis and flow traces instead of being silently skipped. Metal's `[[buffer(0)]]`-style attribute annotations are handled so they can't corrupt what gets extracted. Thanks @FluxKo for the report. (#1121)
 - CodeGraph now indexes legacy **iBatis 2** SQL maps (`<sqlMap>`), not just MyBatis 3 `<mapper>` files. `<select>`/`<insert>`/`<update>`/`<delete>`, iBatis's `<statement>`/`<procedure>`, and `<sql>` fragments inside a `<sqlMap>` become searchable statement symbols — for both namespaced maps and the namespace-less `Map.statement` id style — and `<include>` references resolve to the fragment they pull in, so search, callers, and impact queries return results on iBatis codebases that previously produced no statement symbols at all. Thanks @ESPINS for the report and the reproduction. (#1182)
+- You can now force gitignored first-party source **into** the index with an `include` list in `codegraph.json`. The case this solves: a project tracked by a second VCS (SVN, Perforce, …) alongside Git, where some real source is committed to that VCS and deliberately listed in `.gitignore` so it never lands in Git — git never lists those files, so CodeGraph never indexed them, and neither `includeIgnored` (which only revives *embedded git repositories* inside a gitignored directory) nor `exclude` (its opposite) could help. Add a root `codegraph.json` with, e.g., `{ "include": ["Tools/", "Local/typescript/"] }` and CodeGraph discovers those files directly off disk — overriding `.gitignore` — and indexes them on the full index, incremental `sync`, and file-watching, on both git and non-git projects. Patterns are gitignore-style and matched against project-root-relative paths (a directory, a recursive `**` glob, or a single file). An explicit `exclude` still wins, and built-in skips like `node_modules`, `dist`, and `.git` are never re-included. This complements the existing `exclude` (its opposite — keep tracked files *out*) and `includeIgnored` (opt *in* to gitignored embedded repos).
 
 ### Fixes