docs: Pages site cleanup step 1 - curated publish set + cross-link fixes (#51)

* docs: step 1 of the docs/site cleanup - whitelist Pages site config, fix cross-links to excluded docs, drop game-behavior-reference index bullet

Publish only the curated set (index/building/internals/porting-notes/
dev-process/agentic-development); everything else under docs/ stays in
the repo but out of the Pages build and sitemap. Cross-links from the
published pages to excluded docs now point at GitHub blob URLs so they
still resolve. No content rewrite yet -- steps 2-5 (README update, per-
page descriptions, light copy passes, repo hygiene) remain.

Claude-Session: https://claude.ai/code/session_016TaKy6AAsVUTfjkhrX6CjG

* docs(dev-process): add §6 -- keep PR/git-history noise low

Squash-merge single-purpose/docs PRs, batch same-session docs updates
into one branch instead of one-PR-per-finding, keep unrelated
housekeeping off active branches, declare stacked-PR dependencies, and
triage the open-PR list every session -- close stale PRs (superseded
by newer main content) rather than force-merging or endlessly
rebasing them.

Prompted by this session's PR #26: real conflicts against main because
D191/D193/D149 were all fixed/closed since it was opened; closed
rather than rebased.

docs/dev/agentic-development.md

@@ -106,7 +106,7 @@ issues still outstanding.
 |---|---|
 | Calendar time | 16 days (16 Aug – 1 Sep 2026), one person part-time |
 | Commits on the port | ~223 |
-| Root-caused bugs logged | 162 (`D1`–`D169` in [`findings.md`](findings.md); some later merged or withdrawn) |
+| Root-caused bugs logged | 162 (`D1`–`D169` in [`findings.md`](https://github.com/jkdansereau/goldeneye-pc-port/blob/main/docs/dev/findings.md); some later merged or withdrawn) |
 | Handoff sessions | ~33 (`M-2` … `M-33`) |
 | Game-source files given `#ifdef PORT` ABI edits | 63 files, 241 blocks |
 | New port-layer / tooling files | 128 |
@@ -261,4 +261,5 @@ Honest notes, for anyone weighing whether this transfers.
 
 **Still outstanding** (parked below crash/level work): audio is not
 implemented; several front-end 3D transforms and some text rendering are
-wrong. See [`GRAPHICS-BACKLOG.md`](GRAPHICS-BACKLOG.md).
+wrong. See
+[`GRAPHICS-BACKLOG.md`](https://github.com/jkdansereau/goldeneye-pc-port/blob/main/docs/dev/GRAPHICS-BACKLOG.md).