feat: implement Obsidian MCP Bundle MVP (Phase 1-3)

- Complete project setup with TypeScript, Jest, MCPB manifest
- Implement foundational infrastructure (CLI executor, logger, error handler)
- Add 9 file operation tools for User Story 1
- Full MCP protocol compliance with stdio transport
- Input validation and sanitization for security
- Comprehensive error handling with actionable messages
- Constitutional compliance: all 6 principles satisfied

MVP includes:
- obsidian_create_note, read, append, prepend, delete, move, rename, open, file_info
- Zod validation schemas for all parameters
- 30s timeout configuration with per-command overrides
- Stderr-only logging with sanitized output
- Graceful shutdown handling

Build: ✅ 0 errors, 0 vulnerabilities
Tasks: 48/167 complete (MVP milestone)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/cli/executor.ts

@@ -0,0 +1,117 @@
+/**
+ * CLI Executor for Obsidian commands
+ * Constitutional Principle IV: Defensive Programming
+ * Uses spawn for better streaming and timeout control
+ */
+
+import { spawn } from 'child_process';
+import { CLICommand, CLIResult } from '../utils/types.js';
+import { logger } from '../utils/logger.js';
+import { getCommandTimeout } from '../config/timeouts.js';
+
+/**
+ * Execute an Obsidian CLI command with timeout
+ */
+export async function executeCommand(cmd: CLICommand): Promise<CLIResult> {
+  const timeout = cmd.timeout || getCommandTimeout(cmd.command);
+  logger.debug('Executing CLI command', {
+    command: cmd.command,
+    argCount: cmd.args.length,
+    timeout,
+  });
+
+  return new Promise((resolve) => {
+    const child = spawn(cmd.command, cmd.args, {
+      cwd: cmd.cwd || process.cwd(),
+      shell: true,
+    });
+
+    let stdout = '';
+    let stderr = '';
+    let timedOut = false;
+
+    // Set timeout
+    const timeoutId = setTimeout(() => {
+      timedOut = true;
+      child.kill('SIGTERM');
+      logger.warn('CLI command timed out', {
+        command: cmd.command,
+        timeout,
+      });
+    }, timeout);
+
+    // Collect stdout
+    child.stdout?.on('data', (data) => {
+      stdout += data.toString();
+    });
+
+    // Collect stderr
+    child.stderr?.on('data', (data) => {
+      stderr += data.toString();
+    });
+
+    // Handle completion
+    child.on('close', (code) => {
+      clearTimeout(timeoutId);
+
+      const result: CLIResult = {
+        stdout: stdout.trim(),
+        stderr: stderr.trim(),
+        exitCode: code || 0,
+        timedOut,
+      };
+
+      if (result.exitCode === 0) {
+        logger.debug('CLI command succeeded', {
+          command: cmd.command,
+          outputLength: result.stdout.length,
+        });
+      } else {
+        logger.warn('CLI command failed', {
+          command: cmd.command,
+          exitCode: result.exitCode,
+          timedOut: result.timedOut,
+        });
+      }
+
+      resolve(result);
+    });
+
+    // Handle spawn errors
+    child.on('error', (error) => {
+      clearTimeout(timeoutId);
+      logger.error('CLI command spawn error', { error: error.message });
+
+      resolve({
+        stdout: '',
+        stderr: error.message,
+        exitCode: 1,
+        timedOut: false,
+      });
+    });
+  });
+}
+
+/**
+ * Execute Obsidian CLI command with vault context
+ */
+export async function executeObsidianCommand(
+  subcommand: string,
+  args: string[] = [],
+  options?: { timeout?: number }
+): Promise<CLIResult> {
+  const vaultName = process.env.OBSIDIAN_VAULT;
+
+  if (!vaultName) {
+    throw new Error('OBSIDIAN_VAULT environment variable not set');
+  }
+
+  // Build full command: obsidian <subcommand> --vault <vault_name> <args>
+  const fullArgs = [subcommand, '--vault', vaultName, ...args];
+
+  return executeCommand({
+    command: 'obsidian',
+    args: fullArgs,
+    timeout: options?.timeout,
+  });
+}