feat: expand magic prompts coverage and split generation prompts (#835)

- Add configurable visible/instructions prompt families for commit/PR generation, PR checks/comments flows, and git conflict resolution helpers.
- Refactor prompt sending to explicit visible + synthetic parts instead of newline-based splitting, with legacy override migration for old keys.
- Polish Magic Prompts settings UX with grouped sidebar entries, tooltip-based descriptions, AI icon, and validation that visible prompts cannot be empty across web and VS Code runtimes.

packages/web/server/lib/magic-prompts/routes.js

@@ -0,0 +1,63 @@
+import { createMagicPromptRuntime } from './runtime.js';
+
+export const registerMagicPromptRoutes = (app, dependencies) => {
+  const {
+    fsPromises,
+    path,
+    openchamberDataDir,
+  } = dependencies;
+
+  const runtime = createMagicPromptRuntime({
+    fsPromises,
+    path,
+    filePath: path.join(openchamberDataDir, 'magic-prompts.json'),
+  });
+
+  app.get('/api/magic-prompts', async (_req, res) => {
+    try {
+      const state = await runtime.readPromptState();
+      res.json(state);
+    } catch (error) {
+      res.status(500).json({ error: error instanceof Error ? error.message : 'Failed to read magic prompts' });
+    }
+  });
+
+  app.put('/api/magic-prompts/:id', async (req, res) => {
+    const id = typeof req.params?.id === 'string' ? req.params.id : '';
+    const text = typeof req.body?.text === 'string' ? req.body.text : null;
+    if (text === null) {
+      return res.status(400).json({ error: 'text is required' });
+    }
+
+    try {
+      const state = await runtime.setOverride(id, text);
+      return res.json(state);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      const status = message.includes('Invalid prompt id') || message.includes('too long') || message.includes('cannot be empty') ? 400 : 500;
+      return res.status(status).json({ error: message });
+    }
+  });
+
+  app.delete('/api/magic-prompts/:id', async (req, res) => {
+    const id = typeof req.params?.id === 'string' ? req.params.id : '';
+    try {
+      const state = await runtime.resetOverride(id);
+      return res.json(state);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      const status = message.includes('Invalid prompt id') ? 400 : 500;
+      return res.status(status).json({ error: message });
+    }
+  });
+
+  app.delete('/api/magic-prompts', async (_req, res) => {
+    try {
+      const state = await runtime.resetAllOverrides();
+      return res.json(state);
+    } catch (error) {
+      const message = error instanceof Error ? error.message : String(error);
+      return res.status(500).json({ error: message || 'Failed to reset magic prompts' });
+    }
+  });
+};

packages/web/server/lib/magic-prompts/runtime.js

@@ -0,0 +1,119 @@
+const FILE_VERSION = 1;
+const MAX_PROMPT_TEXT_LENGTH = 200_000;
+const PROMPT_ID_PATTERN = /^[a-z0-9._-]{1,160}$/;
+const isVisiblePromptID = (id) => typeof id === 'string' && id.endsWith('.visible');
+
+const hasOwn = (input, key) => Object.prototype.hasOwnProperty.call(input, key);
+
+const sanitizeOverrides = (value) => {
+  if (!value || typeof value !== 'object' || Array.isArray(value)) {
+    return {};
+  }
+
+  const next = {};
+  for (const [key, entry] of Object.entries(value)) {
+    if (!PROMPT_ID_PATTERN.test(key) || typeof entry !== 'string') {
+      continue;
+    }
+    next[key] = entry;
+  }
+  return next;
+};
+
+export const createMagicPromptRuntime = (dependencies) => {
+  const {
+    fsPromises,
+    path,
+    filePath,
+  } = dependencies;
+
+  let writeLock = Promise.resolve();
+
+  const readPromptState = async () => {
+    try {
+      const raw = await fsPromises.readFile(filePath, 'utf8');
+      const parsed = JSON.parse(raw);
+      const overrides = sanitizeOverrides(parsed?.overrides);
+      return {
+        version: FILE_VERSION,
+        overrides,
+      };
+    } catch (error) {
+      if (error && typeof error === 'object' && error.code === 'ENOENT') {
+        return { version: FILE_VERSION, overrides: {} };
+      }
+      console.warn('Failed to read magic prompts file:', error);
+      return { version: FILE_VERSION, overrides: {} };
+    }
+  };
+
+  const writePromptState = async (state) => {
+    await fsPromises.mkdir(path.dirname(filePath), { recursive: true });
+    await fsPromises.writeFile(filePath, JSON.stringify(state, null, 2), 'utf8');
+  };
+
+  const persist = async (mutator) => {
+    const run = async () => {
+      const current = await readPromptState();
+      const next = await mutator(current);
+      await writePromptState(next);
+      return next;
+    };
+    writeLock = writeLock.then(run, run);
+    return writeLock;
+  };
+
+  const setOverride = async (id, text) => {
+    const normalizedId = typeof id === 'string' ? id.trim() : '';
+    if (!PROMPT_ID_PATTERN.test(normalizedId)) {
+      throw new Error('Invalid prompt id');
+    }
+    if (typeof text !== 'string') {
+      throw new Error('Prompt text must be a string');
+    }
+    if (isVisiblePromptID(normalizedId) && text.trim().length === 0) {
+      throw new Error('Visible prompt text cannot be empty');
+    }
+    if (text.length > MAX_PROMPT_TEXT_LENGTH) {
+      throw new Error('Prompt text is too long');
+    }
+
+    return persist(async (state) => {
+      const nextOverrides = { ...state.overrides, [normalizedId]: text };
+      return {
+        version: FILE_VERSION,
+        overrides: nextOverrides,
+      };
+    });
+  };
+
+  const resetOverride = async (id) => {
+    const normalizedId = typeof id === 'string' ? id.trim() : '';
+    if (!PROMPT_ID_PATTERN.test(normalizedId)) {
+      throw new Error('Invalid prompt id');
+    }
+
+    return persist(async (state) => {
+      if (!hasOwn(state.overrides, normalizedId)) {
+        return state;
+      }
+      const nextOverrides = { ...state.overrides };
+      delete nextOverrides[normalizedId];
+      return {
+        version: FILE_VERSION,
+        overrides: nextOverrides,
+      };
+    });
+  };
+
+  const resetAllOverrides = async () => {
+    return persist(async () => ({ version: FILE_VERSION, overrides: {} }));
+  };
+
+  return {
+    readPromptState,
+    setOverride,
+    resetOverride,
+    resetAllOverrides,
+  };
+};

packages/web/server/lib/opencode/core-routes.js

@@ -161,6 +161,7 @@ export const registerCommonRequestMiddleware = (app, dependencies) => {
       req.path.startsWith('/api/projects') ||
       req.path.startsWith('/api/fs') ||
       req.path.startsWith('/api/git') ||
+      req.path.startsWith('/api/magic-prompts') ||
       req.path.startsWith('/api/prompts') ||
       req.path.startsWith('/api/terminal') ||
       req.path.startsWith('/api/opencode') ||

packages/web/server/lib/opencode/feature-routes-runtime.js

@@ -2,6 +2,7 @@ import { registerFsRoutes } from '../fs/routes.js';
 import { registerQuotaRoutes } from '../quota/routes.js';
 import { registerGitHubRoutes } from '../github/routes.js';
 import { registerGitRoutes } from '../git/routes.js';
+import { registerMagicPromptRoutes } from '../magic-prompts/routes.js';
 import { registerConfigEntityRoutes } from './config-entity-routes.js';
 import { registerSettingsUtilityRoutes } from './core-routes.js';
 import { registerProjectIconRoutes } from './project-icon-routes.js';
@@ -196,6 +197,11 @@ export const createFeatureRoutesRuntime = (dependencies) => {
     registerQuotaRoutes(app, { getQuotaProviders });
     registerGitHubRoutes(app);
     registerGitRoutes(app);
+    registerMagicPromptRoutes(app, {
+      fsPromises,
+      path,
+      openchamberDataDir,
+    });
     registerFsRoutes(app, {
       os,
       path,