docs(guide): add release-prep milestone-viewing workflow to processes.gitea-issues

Document how to view a release milestone's issues in Gitea:
- per-repo web UI filter URL pattern (milestone=<id>)
- cross-repo rollup via issues/search by name
- a copy-paste one-liner that regenerates the current-month
  per-repo links for any YYYY-MM (no hardcoded ids)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/src/main/resources/content/processes/gitea-issues/overview.md

@@ -63,6 +63,29 @@ completed releases, not plans):
   (`&limit=50&page=N`) or older months get truncated (June's newer issues hid Feb–May on the first pass).
 - Rollup any release across repos: `GET /repos/issues/search?milestones=<YYYY-MM>&owner=hiveiq-src`.
 
+### Viewing a milestone (release-prep)
+To scan what a release contains, view its issues per repo in the Gitea web UI:
+
+- **Per-repo, clickable:** `…/hiveiq-src/<repo>/issues?type=all&state=open&milestone=<id>`. The
+  `milestone=` param is the **per-repo numeric id** — Gitea's web filter has no by-name option, so
+  a `2026-07` link differs per repo. Get the id: `GET /repos/hiveiq-src/<repo>/milestones?state=all`
+  → match `title == "<YYYY-MM>"`.
+- **Cross-repo, one query (no ids):** `GET /repos/issues/search?state=open&milestones=<YYYY-MM>&owner=hiveiq-src`
+  (the rollup above) — best for "everything targeted at the release."
+
+**Regenerate the current-month per-repo links** (works for any month — never hardcode ids, they
+rotate each release and close when the milestone does):
+
+```bash
+MONTH=2026-07; TOKEN=<hiveiq token>; BASE=https://hiveiq-gitea.directlx.dev
+for r in $(GIT_SSL_NO_VERIFY=true curl -s "$BASE/api/v1/orgs/hiveiq-src/repos?limit=100" \
+  -H "Authorization: token $TOKEN" | python3 -c "import sys,json;[print(x['name']) for x in json.load(sys.stdin)]"); do
+  GIT_SSL_NO_VERIFY=true curl -s "$BASE/api/v1/repos/hiveiq-src/$r/milestones?state=all&limit=100" \
+    -H "Authorization: token $TOKEN" \
+  | python3 -c "import sys,json;r='$r';b='$BASE';m='$MONTH';[print(f'{r}: {b}/hiveiq-src/{r}/issues?type=all&state=open&milestone='+str(x['id'])) for x in json.load(sys.stdin) if x['title']==m]"
+done
+```
+
 ## Assignment
 - **New issue** → assign `hiveiq` (triage / fix owner).
 - **Fix deployed** → reassign to the verifier and apply **`Verify Fix`**.