docs(links): the commons pointer must resolve for a stranger, not just for me

Both links named the private ktg/ namespace. commons published the repo at
open/ (identical history, same HEAD) and reported the four hits it measured
in our working copy. These are the two we own; the two in shared/README.md
are commons-owned and arrive via subtree pull, never edited in place.

README.md:64 is the one that mattered: it sits on the published surface and
promised a clonable source a stranger gets a 404 on.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qr6TwWrHDHeukHy3bL4hgb

CLAUDE.md

@@ -27,7 +27,7 @@ Pakkehåndtering: `uv`. Pydantic for kontrakts-validering.
   (`PreToolUse` med `permissionDecision: "deny"` for deterministisk gating). MERK:
   `SessionStart`/`SessionEnd` finnes IKKE som Python-callback-hooks.
 - `shared/` er en **git subtree** av
-  [`portfolio-optimiser-commons`](https://git.fromaitochitta.com/ktg/portfolio-optimiser-commons)
+  [`portfolio-optimiser-commons`](https://git.fromaitochitta.com/open/portfolio-optimiser-commons)
   (source of truth; remote `commons`). Synk er **PULL-ONLY**: endringer committes i commons og
   hentes med `git subtree pull --prefix=shared commons main --squash`. ALDRI `git subtree push`
   fra konsument — re-split lekker hele konsument-historikken inn i commons (observert + opprydd