Fix version drift between pom.xml and scripts/codegen/package.json

The sync-codegen-version.sh script used `npm install` which normalizes
semver ranges, stripping prerelease suffixes (e.g. ^1.0.43-0 → ^1.0.43).
Fix by writing the version directly into package.json before running
npm install, matching how sync-cli-version-from-reference-impl.sh
updates pom.xml.

Also fix CapiProxy inconsistent state: defer proxyUrl assignment until
after metadata parsing succeeds.

Agent-Logs-Url: https://github.com/github/copilot-sdk-java/sessions/243ea08c-366e-4ac4-bdb6-939a59a1e755

Co-authored-by: edburns <75821+edburns@users.noreply.github.com>

Author: Copilot

.github/scripts/reference-impl-sync/sync-codegen-version.sh

@@ -63,9 +63,17 @@ if [[ ! -f "$CODEGEN_PKG" ]]; then
 fi
 
 # Update scripts/codegen/package.json with the new version and regenerate the lock file.
-# Intentionally omit --save-exact to preserve the version specifier used by the reference
-# implementation (e.g. a caret range like '^1.0.36-0' rather than an exact pin '1.0.36-0').
+# Write the version string directly into package.json to preserve the exact specifier
+# used by the reference implementation (e.g. '^1.0.43-0').  npm install normalises
+# caret ranges and would silently strip the prerelease suffix, causing a mismatch
+# with pom.xml.
 echo "▸ Updating scripts/codegen/package.json: @github/copilot → ${CLI_VERSION}"
 cd "$CODEGEN_DIR"
-npm install "@github/copilot@${CLI_VERSION}"
+node -e "
+const fs = require('fs');
+const pkg = JSON.parse(fs.readFileSync('package.json', 'utf8'));
+pkg.dependencies['@github/copilot'] = process.argv[1];
+fs.writeFileSync('package.json', JSON.stringify(pkg, null, 2) + '\n');
+" "$CLI_VERSION"
+npm install
 echo "▸ Updated scripts/codegen to @github/copilot@${CLI_VERSION}"

scripts/codegen/package-lock.json

@@ -7,7 +7,7 @@
     "generate:java": "tsx java.ts"
   },
   "dependencies": {
-    "@github/copilot": "^1.0.43",
+    "@github/copilot": "^1.0.43-0",
     "json-schema": "^0.4.0",
     "tsx": "^4.20.6"
   }

scripts/codegen/package.json

@@ -139,7 +139,7 @@ public String start() throws IOException, InterruptedException {
             throw new IOException("Unexpected proxy output: " + line);
         }
 
-        proxyUrl = matcher.group(1);
+        String url = matcher.group(1);
 
         // Parse optional metadata (CONNECT proxy details)
         String metadata = matcher.group(2);
@@ -155,6 +155,8 @@ public String start() throws IOException, InterruptedException {
             }
         }
 
+        // Only set proxyUrl after all parsing succeeds to avoid inconsistent state
+        proxyUrl = url;
         return proxyUrl;
     }