feat(flow): add --resume flag to resume Claude Code sessions

Thread --resume [session-id] through the full CLI pipeline so users
can resume previous Claude Code sessions via Flow.

Author: shtse8

packages/flow/src/commands/flow-command.ts

@@ -27,6 +27,7 @@ export const flowCommand = new Command('flow')
   .option('--dry-run', 'Show what would be done without making changes')
   .option('-p, --print', 'Headless print mode (output only, no interactive)')
   .option('-c, --continue', 'Continue previous conversation (requires print mode)')
+  .option('-r, --resume [session-id]', 'Resume a previous Claude Code session')
   .option('--merge', 'Merge Flow settings with existing settings (default: replace all)')
 
   // Prompt argument

packages/flow/src/commands/flow/execute-v2.ts

@@ -306,6 +306,7 @@ export async function executeFlowV2(
       prompt,
       print: options.print,
       continue: options.continue,
+      resume: options.resume,
     };
 
     // Suppress SIGINT in parent — child process handles its own Ctrl+C.

packages/flow/src/commands/flow/types.ts

@@ -26,6 +26,7 @@ export interface FlowOptions {
   // Execution modes
   print?: boolean;
   continue?: boolean;
+  resume?: string | boolean;
 
   // Attach strategy
   merge?: boolean; // Merge with user settings instead of replacing (default: replace)

packages/flow/src/index.ts

@@ -58,6 +58,7 @@ export function createCLI(): Command {
     .option('--dry-run', 'Show what would be done without making changes')
     .option('-p, --print', 'Headless print mode (output only, no interactive)')
     .option('-c, --continue', 'Continue previous conversation (requires print mode)')
+    .option('-r, --resume [session-id]', 'Resume a previous Claude Code session')
     .option('--merge', 'Merge Flow settings with existing settings (default: replace all)')
 
     .action(async (prompt, options) => {

packages/flow/src/targets/claude-code.ts

@@ -199,7 +199,7 @@ export const claudeCodeTarget: Target = {
   async executeCommand(
     systemPrompt: string,
     userPrompt: string,
-    options: { verbose?: boolean; dryRun?: boolean; print?: boolean; continue?: boolean } = {}
+    options: { verbose?: boolean; dryRun?: boolean; print?: boolean; continue?: boolean; resume?: string | boolean } = {}
   ): Promise<void> {
     // Sanitize and validate inputs
     const sanitizedSystemPrompt = sanitize.yamlContent(systemPrompt);
@@ -220,6 +220,12 @@ Please begin your response with a comprehensive summary of all the instructions
       if (options.continue) {
         dryRunArgs.push('-c');
       }
+      if (options.resume) {
+        dryRunArgs.push('--resume');
+        if (typeof options.resume === 'string') {
+          dryRunArgs.push(options.resume);
+        }
+      }
       dryRunArgs.push('--system-prompt', '"<agent content>"');
       if (sanitizedUserPrompt.trim() !== '') {
         dryRunArgs.push(`"${sanitizedUserPrompt}"`);
@@ -247,6 +253,12 @@ Please begin your response with a comprehensive summary of all the instructions
       if (options.continue) {
         args.push('-c');
       }
+      if (options.resume) {
+        args.push('--resume');
+        if (typeof options.resume === 'string') {
+          args.push(options.resume);
+        }
+      }
 
       args.push('--system-prompt', enhancedSystemPrompt);
       if (options.verbose) {

packages/flow/src/types/cli.types.ts

@@ -84,4 +84,5 @@ export interface RunCommandOptions {
   prompt?: string;
   print?: boolean; // Headless print mode
   continue?: boolean; // Continue previous conversation
+  resume?: string | boolean; // Resume a previous session
 }