rename(telegram-desktop): package ID to telegram

Same pattern already used for claude/claude-desktop: keep the upstream
desktop-id (org.telegram.desktop) and every installed path unchanged, only
rename the Stapler package directory and `name` field. `replaces` stays
self-name-only per the general rule in validate_repo.py (the old-name
carve-over in `replaces` is currently special-cased there for `claude`
only) — anyone with telegram-desktop installed needs `stplr install
telegram` + `stplr remove telegram-desktop` manually.

telegram/stapler-repo.toml

@@ -0,0 +1 @@
+include = "../stapler-repo.toml"