feat(nightly): add nightly build for emacs-29 branch

With nightly runs at midnight, it sometimes takes GitHub Actions over an
hour to start the build. On rare occasion this allows new commits from
the new day sneaking in.

Hence we adjust the scheduled build time for now, until the build tool
can be updated to support picking a target commit based on date limits.

.github/workflows/_prepare.yml

@@ -7,7 +7,7 @@ on:
         description: Git ref to checkout of build-emacs-for-macos
         required: false
         type: string
-        default: "v0.6.38"
+        default: "v0.6.39"
     secrets:
       TAP_REPO_TOKEN:
         description: Personal Access Token for Homebrew Tap repo

.github/workflows/nightly-emacs-28.yml

@@ -2,7 +2,7 @@
 name: Nightly (emacs-28)
 on:
   schedule:
-    - cron: "0 0 * * *"
+    - cron: "0 23 * * *"
   workflow_dispatch:
     inputs:
       git_sha:

.github/workflows/nightly-emacs-29.yml

@@ -0,0 +1,46 @@
+---
+name: Nightly (emacs-29)
+on:
+  schedule:
+    - cron: "0 23 * * *"
+  workflow_dispatch:
+    inputs:
+      git_sha:
+        description: Override Emacs git commit SHA to build
+        required: false
+
+jobs:
+  prepare:
+    name: Prepare
+    uses: ./.github/workflows/_prepare.yml
+    secrets:
+      TAP_REPO_TOKEN: ${{ secrets.TAP_REPO_TOKEN }}
+
+  build:
+    name: Build
+    needs: [prepare]
+    uses: ./.github/workflows/_build.yml
+    with:
+      os: macos-11
+      git_ref: emacs-29
+      git_sha: ${{ github.event.inputs.git_sha }}
+      build_args: --native-comp
+    secrets:
+      APPLE_DEVELOPER_CERTIFICATE_P12_BASE64: ${{ secrets.APPLE_DEVELOPER_CERTIFICATE_P12_BASE64 }}
+      APPLE_DEVELOPER_CERTIFICATE_PASSWORD: ${{ secrets.APPLE_DEVELOPER_CERTIFICATE_PASSWORD }}
+      KEYCHAIN_PASSWORD: ${{ secrets.KEYCHAIN_PASSWORD }}
+      AC_USERNAME: ${{ secrets.AC_USERNAME }}
+      AC_PASSWORD: ${{ secrets.AC_PASSWORD }}
+      AC_PROVIDER: ${{ secrets.AC_PROVIDER }}
+      AC_SIGN_IDENTITY: ${{ secrets.AC_SIGN_IDENTITY }}
+      TAP_REPO_TOKEN: ${{ secrets.TAP_REPO_TOKEN }}
+
+  release:
+    name: Release
+    needs: [build]
+    uses: ./.github/workflows/_release.yml
+    with:
+      plan_artifact: build-plan
+      dmg_artifact: dmg
+    secrets:
+      TAP_REPO_TOKEN: ${{ secrets.TAP_REPO_TOKEN }}

.github/workflows/nightly-master.yml

@@ -2,7 +2,7 @@
 name: Nightly (master)
 on:
   schedule:
-    - cron: "0 0 * * *"
+    - cron: "0 23 * * *"
   workflow_dispatch:
     inputs:
       git_sha: