chore(installer): drop the new code comments added with the install fix

Repository rule: no new code comments; the reasoning belongs in commit
messages. e9c9de775f's message already carries it:
- `(dev)` in CODEWHALE_BUILD_VERSION marks an unstamped checkout. A release
  artifact carries its short SHA, and a Cargo source package carries the
  plain version.
- A forced reinstall that fails puts the moved-aside command back.

This removes the comment added in update.rs and the forced-backup comment
blocks added in both installers. The edited comment that explains when
existing binaries are replaced stays, because it now describes
CODEWHALE_FORCE_REINSTALL.

Comment-only change. Verified: `bash -n scripts/release/install.sh` and
`sh -n web/public/install.sh` pass.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

crates/cli/src/update.rs

@@ -62,10 +62,6 @@ pub fn run_update(beta: bool, check_only: bool, proxy_arg: Option<String>) -> Re
     let channel = ReleaseChannel::from_beta_flag(beta);
     let current_version = env!("CARGO_PKG_VERSION");
     let build_version = env!("CODEWHALE_BUILD_VERSION");
-    // The build script marks an unstamped checkout with `(dev)` and nothing
-    // else: a release artifact carries its short SHA and a Cargo source
-    // package carries the plain version. Only the checkout marker means the
-    // installed file has no published artifact behind it.
     let unreleased_checkout_build = build_version.ends_with(" (dev)");
     let proxy = proxy_arg
         .as_deref()

scripts/release/install.sh

@@ -147,9 +147,6 @@ check_destination() {
 
 # The image is an explicit installer choice; presence never changes Core's
 # Node default. Archives carry notices/source beside any qualified image.
-# Backups this run made under CODEWHALE_FORCE_REINSTALL. A run that fails after
-# moving a command aside puts it back, so a forced install that does not
-# complete never leaves a command missing from the prefix.
 forced_backups=()
 stage=""
 stage_dir=""

web/public/install.sh

@@ -245,9 +245,6 @@ esac
 tmpdir="$(mktemp -d 2>/dev/null || mktemp -d -t codewhale-install)"
 trap 'rm -rf "$tmpdir"' EXIT INT TERM
 
-# Backups this run made under CODEWHALE_FORCE_REINSTALL, newest last. A run that
-# fails after moving a command aside puts it back, so a forced install that does
-# not complete never leaves the command missing from the install directory.
 forced_backups="$tmpdir/.forced-backups"
 : > "$forced_backups"
 
@@ -273,8 +270,6 @@ restore_forced_backups() {
   while IFS= read -r backup; do
     [ -n "$backup" ] || continue
     [ -e "$backup" ] || continue
-    # The name this run generated ends in .bak-<utc-stamp>[-<n>]; the
-    # destination is everything before it.
     destination="$(printf '%s' "$backup" | sed 's/\.bak-[0-9TZ]*\(-[0-9][0-9]*\)\{0,1\}$//')"
     if [ ! -e "$destination" ] && [ ! -L "$destination" ]; then
       mv "$backup" "$destination" && say "Restored $destination: this install did not complete." >&2