Initial commit: Screen Leads app

Screen-capture lead tool: capture agent, Claude vision extractor with
pluggable site recipes (LinkedIn), canonical funnel model, SQLite storage,
FastAPI backend, dashboard, and setup/run scripts.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.env.example

@@ -0,0 +1,20 @@
+# Copy to .env and fill in. Only ANTHROPIC_API_KEY is required.
+ANTHROPIC_API_KEY=sk-ant-...
+
+# Vision model (default is the most capable; sonnet is cheaper for high volume)
+# SCREEN_LEADS_MODEL=claude-opus-4-8
+
+# Capture tuning
+# SCREEN_LEADS_START_DELAY=5      # grace period to focus the browser (0 = off)
+# SCREEN_LEADS_SCROLL_STEPS=6
+# SCREEN_LEADS_SCROLL_AMOUNT=800
+# SCREEN_LEADS_SCROLL_PAUSE=0.8
+# SCREEN_LEADS_WATCH_INTERVAL=2.0
+
+# "stop" (default) ends the run when the front tab is not a LinkedIn profile;
+# "wait" keeps polling instead.
+# SCREEN_LEADS_ON_INVALID_PAGE=stop
+
+# Server
+# SCREEN_LEADS_HOST=127.0.0.1
+# SCREEN_LEADS_PORT=8000