G1 step 1: gemini get, and two TLS connections measured

`gemini get <url>` fetches on a short-lived task (a handshake would trip
the main loop's watchdog; an idle client should cost no stack) and
reports the header, size, certificate fingerprint and heap. First page:
geminiprotocol.net, 20 text/gemini, 1,184 bytes in 0.7-1.1 s.

With IRC connected over TLS, a fetch dips to about 24 KB free during its
handshake, about 36-40 KB after it; nothing leaks. Antenna is down, so
the default aggregator becomes Cosmos.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

docs/milestones/G1.md

@@ -16,7 +16,7 @@ Gemini (geminiprotocol.net): one request per TLS connection on port 1965, the re
 | Q75 | Gemtext rendering: text wrapped to the 40-column screen; `#`/`##`/`###` headings in bold and accent; `*` lists with bullets; `>` quotes indented and muted; preformatted blocks unwrapped, Left/Right to scroll; `=>` links with their label, numbered. |
 | Q76 | Up/Down scroll; Tab and Shift+Tab move between links; Enter follows; Backspace goes back; `g` opens the address line. Links to other protocols show their URL and aren't followed. |
 | Q77 | Back history of 20 URLs in RAM, with scroll positions; going back refetches (or reopens a Saved Page). **Bookmarks** in `/gemini/bookmarks.gmi` (a gemtext page, shown on the start page); `b` adds the current page. Without a card, a built-in start page. |
-| Q78 | Start page: bookmarks, then Saved Pages, then defaults: geminiprotocol.net, a search engine (kennedy.gemi.dev), an aggregator (Antenna). |
+| Q78 | Start page: bookmarks, then Saved Pages, then defaults: geminiprotocol.net, a search engine (kennedy.gemi.dev), an aggregator (Cosmos; Antenna was down when measured). |
 | Q79 | UTF-8 decoded; characters outside the Latin-1 fonts shown as `?`. |
 | Q80 | IRC and Gemini can run together: each fetch opens one connection, reads and closes it. If there isn't memory for a second TLS connection, the fetch fails with a clear message and IRC is untouched. Measured in step 1. |
 | Q81 | Debug aid: `gemini get <url>` prints the status, MIME type, size, certificate fingerprint and the first lines. URL resolution (RFC 3986), the response header and gemtext parsing are host-tested. |
@@ -25,6 +25,12 @@ Gemini (geminiprotocol.net): one request per TLS connection on port 1965, the re
 | Q84 | The start page lists Saved Pages, newest first, grouped by capsule; they open with no network. In a Saved Page, a link to another Saved Page opens the saved copy; other links fetch online if Wi-Fi is up, or say "not saved, offline". A Saved Page shows when it was saved; `r` refreshes it. |
 | Q85 | Saved Pages are deleted from the App only (`d`, with confirmation), never by Storage Clean-up's age rules, like Notes. |
 
+## Measured (step 1)
+
+- `gemini://geminiprotocol.net/`: `20 text/gemini`, 1,184 bytes, TLS handshake 0.7–1.1 s, whole fetch 0.7–1.1 s; kennedy.gemi.dev 1.9 s. The fetch task's stack peaks at about 3.6 KB of 6.
+- **Heap, Debug Build, IRC connected over TLS:** about 68 KB free before a fetch. After the handshake the fetch holds about 32 KB (36–40 KB left); the handshake itself (certificate chain parsed with the 16 KB receive buffer allocated) dips to about **24 KB** for a second or two. Nothing leaks: the heap after matches the heap before.
+- Antenna (`warmedal.se`) doesn't answer, from the PC either; the default aggregator becomes Cosmos (`gemini://skyjake.fi/~Cosmos/`, which redirects to `cosmos.skyjake.fi`).
+
 ## Done when
 
 - `gemini get gemini://geminiprotocol.net/` prints the header, size and fingerprint on the console.