docs(claude): consolidate graphify sections into Context Navigation

Merge the auto-installed "## graphify" block (L. 170-177, written by
`graphify claude install`) into the existing "## Context Navigation
(graphify)" block. Keeps one source of truth: when to invoke graphify,
what to read first (GRAPH_REPORT.md), and the AST-only --update
shortcut after code edits.

Co-Authored-By: Claude <noreply@anthropic.com>

CLAUDE.md

@@ -53,7 +53,8 @@ Apply unless repo-specific instructions override.
 ## Context Navigation (graphify)
 - Use `/graphify query` ONLY for large-scope tasks: multi-file features, complex bug investigations, architectural changes, major refactors.
 - For small tasks (hotfix, typo, single-file change, quick lookup): read files directly — do NOT invoke graphify.
-- When graphify is used, `graphify-out/wiki/index.md` is the navigation entrypoint.
+- Before answering architecture/codebase questions, read `graphify-out/GRAPH_REPORT.md` for god nodes and community structure. If `graphify-out/wiki/index.md` exists, use it as navigation entrypoint.
+- After modifying code files, run `/graphify <path> --update` to keep the graph current (AST-only, no API cost for code-only changes).
 
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