fix(hooks): include caveman-parse.js in standalone installers

[vishnujayvel]

Summary

Fixes #801 (reported by @prpr289).

Standalone hook installers src/hooks/install.sh and src/hooks/install.ps1 copied a HOOK_FILES / $HookFiles list that omitted caveman-parse.js. caveman-mode-tracker.js top-level-requires ./caveman-parse, so a UserPromptSubmit hook installed via those scripts exits 1 on every prompt.

Secondary bug in the same files: remote fallback base URL pointed at .../main/hooks while hooks live under src/hooks/ — every remote fetch 404s.

Changes (exactly two files)

1. src/hooks/install.sh — add caveman-parse.js to HOOK_FILES; set REPO_URL to .../main/src/hooks
2. src/hooks/install.ps1 — add caveman-parse.js to $HookFiles; set $RepoUrl to .../main/src/hooks

Out of scope (intentional)

• cli/install.js already lists caveman-parse.js and pins a ref (v1.10.0) with a checksum integrity gate. Not touched.
• checksums.sha256 not touched.
• Pinning a ref in the shell installers (like cli/install.js does) is left to maintainer preference; this PR is the minimal fix for the broken file list + 404 URL.

Shell installers remain a supported install path for users who run them directly; this keeps that path working.

Test plan

No automated tests cover src/hooks/install.sh / install.ps1 (repo npm test only runs tests/installer/*.test.mjs against cli/install.js). Manual repro + control is the coverage for this change.

Repro (before fix — old file list, no caveman-parse.js)

tmpdir=$(mktemp -d)
# files from pre-fix HOOK_FILES in install.sh
for f in package.json caveman-config.js caveman-activate.js caveman-mode-tracker.js \
         caveman-stats.js caveman-statusline.sh cavecrew-model-overrides.js; do
  cp src/hooks/$f "$tmpdir/"
done
cd "$tmpdir"
echo '{"prompt":"hello","cwd":"/tmp"}' | node caveman-mode-tracker.js
# expected: Error: Cannot find module './caveman-parse' ; exit 1

Observed (Node v26.5.0):

Error: Cannot find module './caveman-parse'
Require stack:
- .../caveman-mode-tracker.js
...
Node.js v26.5.0
EXIT:1