chore: unify build/lint/tests PR comments into one

.github/actions/ci-status-comment/action.yml

@@ -0,0 +1,33 @@
+name: Upsert CI Status Comment
+description: >-
+  Create or update the single unified CI status comment on a PR, replacing only
+  the given section (build | lint | tests). Seeds a skeleton with all three
+  sections the first time it runs, and re-reads/retries so concurrent writers
+  (build vs. Unity Test) never clobber each other's section.
+
+inputs:
+  pr-number:
+    description: Pull request number to comment on.
+    required: true
+  section:
+    description: Which section to replace — one of build, lint, tests.
+    required: true
+  body:
+    description: Markdown for this section (inline badge + message). Rendered as-is between the section markers.
+    required: true
+  github-token:
+    description: Token with pull-requests:write used to read and upsert the comment.
+    required: true
+
+runs:
+  using: composite
+  steps:
+    - name: Upsert unified CI status comment
+      shell: bash
+      env:
+        GH_TOKEN: ${{ inputs.github-token }}
+        REPO: ${{ github.repository }}
+        PR_NUMBER: ${{ inputs.pr-number }}
+        SECTION: ${{ inputs.section }}
+        SECTION_BODY: ${{ inputs.body }}
+      run: bash "$GITHUB_ACTION_PATH/upsert-ci-status.sh"

.github/actions/ci-status-comment/upsert-ci-status.sh

@@ -0,0 +1,153 @@
+#!/usr/bin/env bash
+# Create or update the single unified CI status comment on a PR, replacing only
+# one section (build | lint | tests). All three CI comment workflows call this
+# through the ci-status-comment composite action, so the three separate bot
+# comments collapse into one.
+#
+# The comment is keyed by the hidden <!-- ci-status --> marker and holds three
+# sections, each fenced by its own start/end markers:
+#
+#   <!-- ci-status -->
+#   ### 🚦 CI Status
+#   <!-- ci:build:start -->  …build…  <!-- ci:build:end -->
+#   <!-- ci:lint:start -->   …lint…   <!-- ci:lint:end -->
+#   <!-- ci:tests:start -->  …tests…  <!-- ci:tests:end -->
+#
+# Build and Unity Test run as independent workflows whose comment writers can
+# fire at the same time, so a plain read-modify-write would drop a section or
+# create a duplicate comment. Each attempt collapses any duplicates (keeping the
+# oldest), rewrites only its own section on that comment, then re-reads to
+# confirm the section landed and no duplicate slipped in — retrying otherwise.
+set -euo pipefail
+
+MARKER="<!-- ci-status -->"
+HEADER="### 🚦 CI Status"
+BOT="github-actions[bot]"
+START="<!-- ci:${SECTION}:start -->"
+END="<!-- ci:${SECTION}:end -->"
+
+# Neutral "waiting" placeholder for a section that has not reported yet. Used
+# only when seeding a brand-new comment; a real run always overwrites its own.
+section_default() {
+  case "$1" in
+    build) printf '![Build](https://img.shields.io/badge/Build-Waiting-lightgrey?logo=unity&logoColor=white&style=for-the-badge)\n\n_Waiting for the build to start…_' ;;
+    lint)  printf '![Lint](https://img.shields.io/badge/Lint-Waiting-lightgrey?logo=jetbrains&logoColor=white&style=for-the-badge)\n\n_Waiting for lint to start…_' ;;
+    tests) printf '![Tests](https://img.shields.io/badge/Tests-Waiting-lightgrey?logo=codecov&logoColor=white&style=for-the-badge)\n\n_Waiting for tests to start…_' ;;
+  esac
+}
+
+# One section, fenced by its start/end markers.
+wrap_section() { printf '<!-- ci:%s:start -->\n%s\n<!-- ci:%s:end -->' "$1" "$2" "$1"; }
+
+# A fresh comment with every section defaulted to "waiting".
+skeleton() {
+  printf '%s\n%s\n\n%s\n\n%s\n\n%s\n' \
+    "$MARKER" "$HEADER" \
+    "$(wrap_section build "$(section_default build)")" \
+    "$(wrap_section lint  "$(section_default lint)")" \
+    "$(wrap_section tests "$(section_default tests)")"
+}
+
+# Emit the section body for this run to a file so awk can splice it verbatim,
+# free of shell quoting concerns. Parts of the body (lint findings, failed test
+# names) originate in the untrusted pull_request job, so drop any line shaped
+# like a section marker before writing it — a body line must never open or close
+# a section fence, or it would scramble the comment structure / wedge the survive
+# check below.
+printf '%s\n' "$SECTION_BODY" \
+  | grep -vE '^[[:space:]]*<!-- ci[-:][^>]*-->[[:space:]]*$' > section_body.md || true
+WANT="$(cat section_body.md)"
+
+# Replace the content between START and END in $1 with section_body.md.
+replace_section() {
+  awk -v s="$START" -v e="$END" -v f="section_body.md" '
+    $0==s { print; while ((getline line < f) > 0) print line; close(f); skip=1; next }
+    $0==e { print; skip=0; next }
+    skip  { next }
+          { print }
+  ' <<< "$1"
+}
+
+# Trimmed content currently between START and END in $1 (for the survive check).
+extract_section() {
+  awk -v s="$START" -v e="$END" '
+    $0==s { grab=1; next }
+    $0==e { grab=0; next }
+    grab  { print }
+  ' <<< "$1"
+}
+
+# Normalise the comment list to a flat array, whether `--paginate --slurp` hands
+# back a flat array of comments or an array of per-page arrays.
+flatten_pages() { jq -c '[.[] | if type=="array" then .[] else . end]' <<< "$1"; }
+
+# IDs of every marker-bearing bot comment on the PR, oldest first. Flattened
+# first so sort_by orders globally rather than only within a page.
+marker_ids() {
+  jq -r --arg m "$MARKER" --arg bot "$BOT" \
+    '[.[] | select(.user.login==$bot and (.body|contains($m)))] | sort_by(.id) | .[].id' <<< "$(flatten_pages "$1")"
+}
+
+for attempt in 1 2 3 4 5; do
+  COMMENTS=$(gh api "/repos/$REPO/issues/$PR_NUMBER/comments" --paginate --slurp)
+  IDS=()
+  while IFS= read -r line; do [ -n "$line" ] && IDS+=("$line"); done <<< "$(marker_ids "$COMMENTS")"
+  COMMENT_ID="${IDS[0]:-}"
+
+  # Collapse accidental duplicates from a create race: keep the oldest, drop the rest.
+  if [ "${#IDS[@]}" -gt 1 ]; then
+    for extra in "${IDS[@]:1}"; do
+      echo "Deleting duplicate CI status comment $extra."
+      gh api -X DELETE "/repos/$REPO/issues/comments/$extra" >/dev/null || true
+    done
+  fi
+
+  if [ -n "$COMMENT_ID" ]; then
+    CURRENT_BODY=$(jq -r --arg id "$COMMENT_ID" '.[] | select(.id==($id|tonumber)) | .body' <<< "$(flatten_pages "$COMMENTS")")
+  else
+    CURRENT_BODY=""
+  fi
+
+  # No unified comment yet, or one missing our section markers: start clean so
+  # all three sections are always present.
+  if [ -z "$CURRENT_BODY" ] || ! grep -qF "$START" <<< "$CURRENT_BODY"; then
+    CURRENT_BODY="$(skeleton)"
+  fi
+
+  NEW_BODY="$(replace_section "$CURRENT_BODY")"
+
+  if [ -z "$COMMENT_ID" ]; then
+    RESULT=$(jq -n --arg b "$NEW_BODY" '{body:$b}' \
+      | gh api -X POST "/repos/$REPO/issues/$PR_NUMBER/comments" --input -)
+    COMMENT_ID=$(jq -r '.id' <<< "$RESULT")
+  else
+    jq -n --arg b "$NEW_BODY" '{body:$b}' \
+      | gh api -X PATCH "/repos/$REPO/issues/comments/$COMMENT_ID" --input - >/dev/null
+  fi
+
+  # Re-read and confirm our section landed on the surviving comment, and that no
+  # concurrent writer left a duplicate behind.
+  sleep 1
+  RECHECK=$(gh api "/repos/$REPO/issues/$PR_NUMBER/comments" --paginate --slurp)
+  RIDS=()
+  while IFS= read -r line; do [ -n "$line" ] && RIDS+=("$line"); done <<< "$(marker_ids "$RECHECK")"
+  LIVE_BODY=$(jq -r --arg id "$COMMENT_ID" '.[] | select(.id==($id|tonumber)) | .body' <<< "$(flatten_pages "$RECHECK")")
+
+  # Success means our section landed on the comment we wrote — nothing more.
+  # Duplicate collapsing is best-effort cleanup (the DELETE above may lack
+  # permission); a duplicate we could not remove must not block reporting that
+  # already succeeded, or every run would burn all 5 attempts and warn forever.
+  if [ "$(extract_section "$LIVE_BODY")" = "$WANT" ]; then
+    echo "CI status '$SECTION' section updated (attempt $attempt)."
+    if [ "${#RIDS[@]}" -gt 1 ]; then
+      echo "A duplicate CI status comment remains (could not be deleted); it will be retried next run."
+    fi
+    exit 0
+  fi
+
+  echo "Section '$SECTION' not settled (attempt $attempt); retrying."
+  sleep $((attempt * 2))
+done
+
+echo "::warning::Could not confirm the '$SECTION' CI status section after 5 attempts."
+exit 0