learn-excalidraw-stylelisted

# Learn from a new Excalidraw example Folds user-designated `.excalidraw` files into the style knowledge behind the `arkitect-excalidraw` skill. It only ever runs when the user asks for it — never learn from a scene just because you happened to read one. Plugin root: `${CLAUDE_PLUGIN_ROOT}`. Work from `${CLAUDE_PLUGIN_ROOT}/skills/arkitect-excalidraw`. This is what turns the shipped guide from *defaults* into *this user's style*. The shipped record already carries real evidence: version 1, 9 scenes, 3,270 elements, learned 2026-09-08. (Before that first learning run, `source-analysis.json` was version 0 with an empty corpus and every convention marked `default` — that state shipped in older releases and would reappear if the file were deleted, but it is not what a fresh install of this repository has today.) A further run merges into the current version-1 record rather than replacing it. Scratch space is `<repo root>/.analysis/` — gitignored, and where the test suite looks for `sources.local.json`. Its `files` key is the designated list. ## Rules - **Read-only.** Never modify, rename, move or reformat an example. Record its SHA-256 before and after and confirm they match. - **Explicit designation only.** The user names the files. Do not scan directories for candidates. - **Nothing confidential enters the repository.** Element text, file names, paths, frame names, links and image payloads stay out. `build-knowledge.mjs` enforces this — it emits structural statist