fix: simplify updater to @mosaic/mosaic only, add explicit tea repo/login flags (#387)

BREAKING CHANGE: Remove legacy @mosaic/cli fallback from update-checker.
The updater now targets only @mosaic/mosaic — legacy package compatibility
is out of scope per approved breaking change.

- update-checker.ts: remove LEGACY_PKG, INSTALLED_PACKAGE_ORDER, candidate
  iteration, and cache key comparison. Single query for @mosaic/mosaic only.
- update-checker.test.ts: remove legacy fallback and cross-contamination
  tests. Add test asserting no @mosaic/cli queries are made.
- pr-merge.sh: add --repo and --login flags to tea merge command; resolve
  OWNER/REPO before case block.
- issue-close.sh: add --repo and --login flags to tea issue commands;
  resolve OWNER/REPO after detect_platform.
- pr-ci-wait.sh: no changes needed (uses curl, not tea).
- detect-platform.sh: no changes needed (provides get_repo_owner/name).

Ref: #387

packages/mosaic/framework/tools/git/issue-close.sh

@@ -45,6 +45,8 @@ fi
 
 # Detect platform and close issue
 detect_platform
+OWNER=$(get_repo_owner)
+REPO=$(get_repo_name)
 
 if [[ "$PLATFORM" == "github" ]]; then
     if [[ -n "$COMMENT" ]]; then
@@ -54,9 +56,9 @@ if [[ "$PLATFORM" == "github" ]]; then
     echo "Closed GitHub issue #$ISSUE_NUMBER"
 elif [[ "$PLATFORM" == "gitea" ]]; then
     if [[ -n "$COMMENT" ]]; then
-        tea issue comment "$ISSUE_NUMBER" "$COMMENT"
+        tea issue comment "$ISSUE_NUMBER" "$COMMENT" --repo "$OWNER/$REPO" --login "${GITEA_LOGIN:-mosaicstack}"
     fi
-    tea issue close "$ISSUE_NUMBER"
+    tea issue close "$ISSUE_NUMBER" --repo "$OWNER/$REPO" --login "${GITEA_LOGIN:-mosaicstack}"
     echo "Closed Gitea issue #$ISSUE_NUMBER"
 else
     echo "Error: Unknown platform"

packages/mosaic/framework/tools/git/pr-merge.sh

@@ -89,6 +89,8 @@ if [[ "$SKIP_QUEUE_GUARD" != true ]]; then
 fi
 
 PLATFORM=$(detect_platform)
+OWNER=$(get_repo_owner)
+REPO=$(get_repo_name)
 
 case "$PLATFORM" in
     github)
@@ -97,8 +99,7 @@ case "$PLATFORM" in
         eval "$CMD"
         ;;
     gitea)
-        # tea pr merge syntax
-        CMD="tea pr merge $PR_NUMBER --style squash"
+        CMD="tea pr merge $PR_NUMBER --style squash --repo $OWNER/$REPO --login ${GITEA_LOGIN:-mosaicstack}"
 
         # Delete branch after merge if requested
         if [[ "$DELETE_BRANCH" == true ]]; then