Sweep stale Ctrl+P references after native-first cleanup

PR #36 rebound fuzzy-find from Ctrl+P (native command-line history)
to ,ff, but four user-facing sites still told people to press Ctrl+P:

- install.sh interactive menu (ripgrep description, fzf description)
- QUICKSTART.md "Find things" block
- .github/demo.tape (the script that regenerates the README hero GIF)

Three text fixes; the .tape update keeps a future regenerate honest.
The binary .github/demo.gif still shows Ctrl+P — regenerating it
requires the original /tmp/demo-project fixture which isn't in repo,
so that's left for a follow-up.

Closes #79

.github/demo.tape

@@ -24,8 +24,8 @@ Type "vim server.py"
 Enter
 Sleep 3.5s
 
-# ── 2. Fuzzy find files (Ctrl+p → type → select) ──────────────────────────
-Ctrl+p
+# ── 2. Fuzzy find files (,ff → type → select) ────────────────────────────
+Type ",ff"
 Sleep 1.5s
 Type "route"
 Sleep 2.5s

CHANGELOG.md

@@ -23,6 +23,11 @@
 
 ### Fixed
 
+- `install.sh` interactive menu and QUICKSTART now show `,ff` (current
+  fuzzy-find binding) instead of the stale `Ctrl+p` left over from the
+  native-first cleanup; `.github/demo.tape` updated to match (the
+  binary GIF still shows `Ctrl+p` until someone regenerates it from a
+  fresh fixture)
 - README badge and `install.sh` recommend Vim 8.1+ instead of 8.0+ —
   the runtime conditionally relies on patches `8.1.0360` (diffopt) and
   `8.1.1517` (completeopt+=popup), so 8.0 users hit option errors

QUICKSTART.md

@@ -45,7 +45,7 @@ Esc             back to Normal
 ## Find things
 
 ```
-Ctrl+p          fuzzy find file (git-aware)
+,ff             fuzzy find file (git-aware)
 ,rg             ripgrep project
 ,b              search buffers
 ,fh             recent files

install.sh

@@ -748,11 +748,11 @@ fi
 # ── System tools ─────────────────────────────────────────────────────────────
 if [[ $HAS_PKG_MGR -eq 1 ]]; then
     _I_RIPGREP=$_idx
-    _ITEMS+=("ripgrep|,rg / ,rG project-wide search · powers Ctrl+p preview|1")
+    _ITEMS+=("ripgrep|,rg / ,rG project-wide search · powers FZF preview|1")
     : $(( _idx++ ))
 
     _I_FZF=$_idx
-    _ITEMS+=("fzf|Ctrl+p fuzzy file search · ,b buffers · ,rt tag search|1")
+    _ITEMS+=("fzf|,ff fuzzy file search · ,b buffers · ,rt tag search|1")
     : $(( _idx++ ))
 
     _I_CTAGS=$_idx