fix ai title generation and remove separate rewrite section

- Remove the standalone "AI Rewrite" section from the editor panel.
  The existing title and description AI buttons already flush the step
  first, so they rewrite whatever the user has typed in those fields.

- Never pass a generic fallback title ("Screen capture", "Window
  capture", "Region capture", "Capture") as the AI title candidate or
  as step content. It is now treated as "(not set — generate a
  specific action title)" so the AI always produces something real.

- hasRichCaptureContext now counts any non-trivial app name or window
  title as sufficient context, instead of requiring non-browser noise.

- Prompt rules updated: "NEVER output Screen/Window/Region capture",
  separate paths for improving a user draft vs generating from context,
  and clearer guidance when context is limited (use app/window name).

- isPlaceholderTitle helper guards summarizeStepForAi so a
  default-titled step presents itself as empty to the AI.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

app/renderer/editor.js

@@ -167,7 +167,6 @@ class GuideEditor {
     const buttons = [
       this.dom?.titleAiBtn,
       this.dom?.descAiBtn,
-      this.dom?.rewriteAiBtn,
       ...(this.dom?.blocksList ? [...this.dom.blocksList.querySelectorAll('button[data-ai-action]')] : []),
     ].filter(Boolean);
     for (const button of buttons) {
@@ -223,36 +222,6 @@ class GuideEditor {
     return this.runAiGeneration('all', { button });
   }
 
-  async runTextRewrite(button = null) {
-    if (!this.isAiEnabled()) {
-      this.onToast('Enable AI in Settings first.', { error: true });
-      return;
-    }
-    const text = this.dom?.rewriteInput?.value?.trim();
-    if (!text) {
-      this.onToast('Type some text to rewrite first.', { error: true });
-      return;
-    }
-    if (button) setButtonLoading(button, true, 'Rewriting…');
-    try {
-      const result = await api.ai.rewriteText({
-        text,
-        guideTitle: this.guide?.title || '',
-        stepTitle: this.currentStep?.title || '',
-      });
-      if (!result || !result.ok) {
-        this.onToast(result?.reason || 'Rewrite failed.', { error: true });
-        return;
-      }
-      if (this.dom?.rewriteInput) this.dom.rewriteInput.value = result.text;
-      this.onToast('Text rewritten.');
-    } catch (err) {
-      this.onToast(err.message || 'Rewrite failed.', { error: true });
-    } finally {
-      if (button) setButtonLoading(button, false);
-    }
-  }
-
   async generateBlockWithAi(kind, block, button = null) {
     if (!block) return null;
     return this.runAiGeneration('block', { blockId: block.id, button });
@@ -442,21 +411,6 @@ class GuideEditor {
             this.dom.addTableBlockBtn = el('button', { type: 'button' }, '+ Table'),
           ),
         ),
-        el('section', {},
-          el('div.row', { style: { justifyContent: 'space-between', alignItems: 'center' } },
-            el('h3', { style: { margin: 0 } }, 'AI Rewrite'),
-            this.dom.rewriteAiBtn = el('button.ai', {
-              type: 'button',
-              title: 'Rewrite the text below with AI',
-              dataset: { aiAction: 'rewrite', aiTitle: 'Rewrite with AI' },
-            }, 'Rewrite'),
-          ),
-          this.dom.rewriteInput = el('textarea', {
-            rows: 3,
-            placeholder: 'Type something to improve…',
-            style: { width: '100%', resize: 'vertical' },
-          }),
-        ),
         el('section', {},
           el('h3', {}, 'Guide'),
           this.dom.guideSummary = el('div.muted', {}),
@@ -629,8 +583,6 @@ class GuideEditor {
     });
     this.dom.descAiBtn.addEventListener('click', () => this.generateDescriptionWithAi(this.dom.descAiBtn));
 
-    this.dom.rewriteAiBtn.addEventListener('click', () => this.runTextRewrite(this.dom.rewriteAiBtn));
-
     this.dom.descEditor.addEventListener('paste', (e) => {
       // Keep pasted text simple; backend sanitization will handle the rest.
       e.preventDefault();