Add context windows, web search, streamed answers, overlay move/resize; overhaul docs

- Context windows (contexts/*.yaml) scope answers to a defined domain
- Optional DuckDuckGo web search behind ai.web_search.enabled (default off)
- Stream partial answers into the overlay at first-token time
- Default Whisper to local base.en (~9x faster); offline model loading
- Priority-ordered loopback detection (BlackHole > Teams device)
- Overlay: drag interior to move, edges to resize
- Stop tracking model binaries (models/ is gitignored)
- README/CLAUDE.md overhaul + tracked config.example.yaml

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

main.py

@@ -5,6 +5,7 @@ Meeting Assistant - Real-time AI Copilot for Meetings
 
 import sys
 import os
+import time
 import yaml
 import threading
 import logging
@@ -255,16 +256,29 @@ class MeetingAssistant:
 
         try:
             context = self.context_manager.get_context()
-            result = self.ai_engine.answer_question(question, context, source)
+
+            # Stream the answer into the overlay as it generates: first words
+            # appear at first-token time instead of after the full generation.
+            asked_by = speaker or ("You" if source == "microphone" else "Them")
+            shown_q = f"({asked_by}) {question}"
+            suggested_early = self.ai_engine.is_suggested(question)
+            t_start = time.time()
+            first_shown = [False]
+
+            def on_partial(text_so_far):
+                if not first_shown[0]:
+                    first_shown[0] = True
+                    print(f"   ⚡ first words on screen after {time.time() - t_start:.1f}s")
+                self.overlay.show_answer(text_so_far + " ▌", shown_q, suggested_early)
+
+            result = self.ai_engine.answer_question(
+                question, context, source, on_partial=on_partial)
 
             if not result or not result.get("text"):
                 return  # interrupted or empty
 
             answer = result["text"]
             suggested = result.get("suggested", False)
-
-            asked_by = speaker or ("You" if source == "microphone" else "Them")
-            shown_q = f"({asked_by}) {question}"
             self.overlay.show_answer(answer, shown_q, suggested)
             self.logger.info(f"Q [{asked_by}]: {question}")
             self.logger.info(f"A: {answer}")
@@ -305,7 +319,10 @@ class MeetingAssistant:
                 self.ai_engine.interrupt()
             self.answering = True
         try:
-            answer = self.ai_engine.answer_from_image(image_path)
+            answer = self.ai_engine.answer_from_image(
+                image_path,
+                on_partial=lambda t: self.overlay.show_answer(
+                    t + " ▌", "Screen question", suggested=False))
             if not answer:
                 return
             self.overlay.show_answer(answer, "Screen question", suggested=False)