Auto-set the build number from git; bump to 2.1

Add Scripts/update_build_number.sh (the shared indie build script) and wire it into both targets as a postBuildScripts phase. On each build it sets CFBundleVersion to the git commit count, writes a BuildDate key (surfaced by IndieAbout), and tags the marketing version. Run as a post-build phase rather than post-compile so it lands after the Info.plist/dSYM exist, which also avoids an Xcode 26 build cycle. Bumps MARKETING_VERSION to 2.1.

Claude-Session: https://claude.ai/code/session_01A9CfUa4E9Zd5swfoNsYPs7

project.yml

@@ -11,7 +11,7 @@ settings:
   base:
     SWIFT_VERSION: "6.0"
     DEVELOPMENT_TEAM: ${APPLE_TEAM_ID}
-    MARKETING_VERSION: "2.0"
+    MARKETING_VERSION: "2.1"
     CURRENT_PROJECT_VERSION: "1"
     ENABLE_USER_SCRIPT_SANDBOXING: "NO"
 
@@ -47,6 +47,14 @@ targets:
       - package: IndieAbout
       - package: Yams
       - target: Workouts Watch App
+    postBuildScripts:
+      - script: '"${SRCROOT}/Scripts/update_build_number.sh"'
+        name: Update Build Number
+        shell: /bin/sh
+        basedOnDependencyAnalysis: false
+        inputFiles:
+          - $(TARGET_BUILD_DIR)/$(INFOPLIST_PATH)
+          - $(DWARF_DSYM_FOLDER_PATH)/$(DWARF_DSYM_FILE_NAME)/Contents/Info.plist
     settings:
       base:
         PRODUCT_BUNDLE_IDENTIFIER: dev.rzen.indie.Workouts
@@ -70,6 +78,14 @@ targets:
         excludes:
           - "Resources/Info-*.plist"
           - "Resources/*.entitlements"
+    postBuildScripts:
+      - script: '"${SRCROOT}/Scripts/update_build_number.sh"'
+        name: Update Build Number
+        shell: /bin/sh
+        basedOnDependencyAnalysis: false
+        inputFiles:
+          - $(TARGET_BUILD_DIR)/$(INFOPLIST_PATH)
+          - $(DWARF_DSYM_FOLDER_PATH)/$(DWARF_DSYM_FILE_NAME)/Contents/Info.plist
     settings:
       base:
         PRODUCT_BUNDLE_IDENTIFIER: dev.rzen.indie.Workouts.watchkitapp