docs(demo): switch to brogrammer theme; open with hello there

Two changes:

- VHS theme moves from Catppuccin Mocha to Brogrammer (slightly higher
  contrast against the Claude TUI's red accents).
- First probe is now a plain `hello there` prompt to claude instead of
  a curl to an allowlisted host. The reply proves api.anthropic.com is
  reachable through pipelock end-to-end (bumped TLS, DLP scan,
  forward) -- a stronger baseline than a static curl, and a more
  honest "the agent works" beat before the three block scenarios.

README copy updated to match. GIF re-recorded and re-encoded
(960px / 10fps / 64-color palette, 2.2 MB).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

README.md

@@ -10,11 +10,14 @@ Run multiple Claude Code agents on your own machine, each scoped to its own secr
 
 ![pipelock and git-gate blocking exfil attempts against a live bottle](docs/demo.gif)
 
-Four probes against a real bottle, end-to-end:
-pipelock forwards a clean HTTPS GET to an allowlisted host,
-blocks a GET to a non-allowlisted host,
-blocks a POST whose body carries a credential pattern;
-git-gate rejects a push containing a leaked key.
+Four moments from a real bottle, end-to-end:
+claude responds to `hello there` — proof api.anthropic.com routes
+through pipelock's bumped TLS;
+a `! curl` to a non-allowlisted host is refused at the host filter;
+a `! curl POST` carrying a credential-shaped body is refused by the
+DLP body scanner;
+a `git push` of a file containing a leaked-looking key is rejected
+by git-gate's gitleaks pre-receive hook.
 Run it yourself with `bash scripts/demo.sh`.
 
 ## Why "claude-bottle"?