0.9.0 is rebuilt from today's main, so it carries today's fixes

JP's call: rebuild 0.9.0 rather than wait for 0.9.1. It has never been public, so the
release is recut from main: Python 3.14 inside the downloads, the corrected written
pages inside the app, companion and room server as the only names for those types, and
the legend that fits a PicoCalc.

[Unreleased] folds into the 0.9.0 entry. On a first release there is nothing for those
changes to have changed from, so they are not listed as changes; the entry gains the one
fact a reader needs, that pipx works on Python 3.10 to 3.14.

The release workflow writes the install half of the notes from its own template, which
still had the two lines fixed by hand on the first 0.9.0 page: "every Mac since 2020",
and "every file below" for a SHA256SUMS that lists only the binaries. Both are fixed at
the source. The changelog extraction also stops carrying the link definitions at the
foot of CHANGELOG.md into the notes.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

.github/workflows/github-release.yml

@@ -127,6 +127,7 @@ jobs:
           awk -v v="$VERSION" '
               $0 ~ "^## \\[" v "\\]" {found=1; next}
               found && /^## \[/ {exit}
+              found && /^\[[^]]+\]: / {next}
               found {print}
             ' CHANGELOG.md > notes.md
           if ! grep -q '[^[:space:]]' notes.md; then
@@ -166,7 +167,7 @@ jobs:
           ./meshterm
           ```
 
-          That is the Apple silicon build — every Mac since 2020. On an Intel Mac, swap
+          That is the build for Apple silicon Macs (M1 and later). On an Intel Mac, swap
           `arm64` for `x64`.
 
           **Linux** — the same three lines with `linux-x64`, or `linux-arm64` on a uConsole
@@ -186,7 +187,7 @@ jobs:
           .\meshterm-@VERSION@-windows-x64.exe
           ```
 
-          Every file below is listed in `SHA256SUMS`. The version-less copies —
+          Every binary below is listed in `SHA256SUMS`. The version-less copies —
           `meshterm-macos-arm64` and its four siblings — are the same binaries under a name
           that never changes, for anything that wants whichever release is newest without
           being told its number. [Installing with pip or pipx, and the rest of the