FEAT: Add availabilityService (#81)

* auto and fallback work

* test fixes

* fixes

* Show model dialog even if there's no more fallback option

* fix tests

* fix failing test

* disable showInDialog for model in settings

* revert package-lock.json

* remove dup line

---------

Co-authored-by: Sehoon Shon <sshon@google.com>

packages/cli/src/config/settings.test.ts

@@ -291,7 +291,7 @@ describe('Settings Loading and Merging', () => {
         theme: 'legacy-dark',
         vimMode: true,
         contextFileName: 'LEGACY_CONTEXT.md',
-        model: 'gemini-pro',
+        model: 'gemini-2.5-pro',
         mcpServers: {
           'legacy-server-1': {
             command: 'npm',
@@ -329,7 +329,7 @@ describe('Settings Loading and Merging', () => {
           fileName: 'LEGACY_CONTEXT.md',
         },
         model: {
-          name: 'gemini-pro',
+          name: 'gemini-2.5-pro',
         },
         mcpServers: {
           'legacy-server-1': {
@@ -1960,7 +1960,7 @@ describe('Settings Loading and Merging', () => {
           usageStatisticsEnabled: false,
         },
         model: {
-          name: 'gemini-pro',
+          name: 'gemini-2.5-pro',
         },
         context: {
           fileName: 'CONTEXT.md',
@@ -1999,7 +1999,7 @@ describe('Settings Loading and Merging', () => {
         vimMode: true,
         theme: 'dark',
         usageStatisticsEnabled: false,
-        model: 'gemini-pro',
+        model: 'gemini-2.5-pro',
         contextFileName: 'CONTEXT.md',
         includeDirectories: ['/src'],
         sandbox: true,