fix(lint): fix all sonarcloud detected issues (#279)

* fix(ci): replace broad permissions with specific scopes in workflows

Replace read-all/write-all with minimum required permission scopes
across all GitHub Actions workflows to follow the principle of least
privilege (SonarCloud rule githubactions:S8234).

* fix(shell): use [[ instead of [ for conditional tests

Replace single brackets with double brackets in bash conditional
expressions across 14 files (28 changes). All scripts use bash
shebangs so [[ is safe everywhere (SonarCloud rule shelldre:S7688).

* fix(shell): add explicit return statements to functions

Add return 0 as the last statement in ~46 shell functions across
17 files that previously relied on implicit return codes
(SonarCloud rule shelldre:S7682).

* fix(shell): assign positional parameters to local variables

Replace direct $1/$2/$3 usage with named local variables in _log(),
msg(), msg_err(), msg_done(), msg_run(), msg_ok(), and array_diff()
(SonarCloud rule shelldre:S7679).

* fix(python): replace dict() constructor with literal

Use {} instead of dict() for empty dictionary initialization
(SonarCloud rule python:S7498).

* fix(shell): fix husky shebang and tolerate npm outdated exit code

* docs(shell): add function docstring comments

* fix(shell): fix heredoc indentation in x-sonarcloud

* feat(python): add ruff linter and formatter configuration

* fix(ci): align megalinter config with biome, ruff, and shfmt settings

* fix(ci): disable black and yaml-prettier in megalinter config

* chore(ci): update ruff-pre-commit to v0.15.0 and fix hook name

* fix(scripts): check for .git dir before skipping clone in install-fonts

* fix(shell): address code review issues in scripts and shared.sh

- Guard wezterm show-keys failure in create-wezterm-keymaps.sh
- Stop masking git failures with return 0 in install-cheat-purebashbible.sh
- Add missing shared.sh source in install-xcode-cli-tools.sh
- Replace exit 1 with return 1 in sourced shared.sh

* fix(scripts): address code review and security findings

- Guard wezterm show-keys failure in create-wezterm-keymaps.sh
- Stop masking git failures with return 0 in install-cheat-purebashbible.sh
- Add missing shared.sh source in install-xcode-cli-tools.sh
- Replace exit 1 with return 1 in sourced shared.sh
- Remove shell=True subprocess calls in x-git-largest-files.py

* style(shell): apply shfmt formatting and add args to pre-commit hook

* fix(python): suppress bandit false positives in x-git-largest-files

* fix(python): add nosemgrep suppression for check_output call

* feat(format): add prettier for YAML formatting

Install prettier, add .prettierrc.json config (200-char width, 2-space
indent, LF endings), .prettierignore, yarn scripts (lint:prettier,
fix:prettier, format:yaml), and pre-commit hook scoped to YAML files.

* style(yaml): apply prettier formatting

* fix(scripts): address remaining code review findings

- Python: use list comprehension to filter empty strings instead of
  slicing off the last element
- create-wezterm-keymaps: write to temp file and mv for atomic updates
- install-xcode-cli-tools: fix shellcheck source directive path

* fix(python): sort imports alphabetically in x-git-largest-files

* fix(lint): disable PYTHON_ISORT in MegaLinter, ruff handles it

* chore(git): add __pycache__ to gitignore

* fix(python): rename ambiguous variable l to line (E741)

* style: remove trailing whitespace and blank lines

* style(fzf): apply shfmt formatting

* style(shell): apply shfmt formatting

* docs(plans): add design documents

* style(docs): add language specifier to fenced code block

* feat(lint): add markdown-table-formatter to dev tooling

Add markdown-table-formatter as a dev dependency with yarn scripts
(lint:md-table, fix:md-table) and a local pre-commit hook to
automatically format markdown tables on commit.

scripts/install-cheat-purebashbible.sh

@@ -12,6 +12,7 @@ PBB_SYNTAX="syntax: bash"
 PBB_TAGS="tags: [bash]"
 PBB_TEMP_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/cheat/pbb"
 
+# Verify required tools are installed
 check_required_tools()
 {
   for t in "${PBB_REQUIRED_TOOLS[@]}"; do
@@ -20,32 +21,37 @@ check_required_tools()
       exit 1
     fi
   done
+  return 0
 }
 
+# Clone or update the pure-bash-bible repository
 clone_or_update_repo()
 {
-  if [ ! -d "$PBB_TEMP_DIR/.git" ]; then
+  if [[ ! -d "$PBB_TEMP_DIR/.git" ]]; then
     msg_run "Starting to clone $PBB_GIT"
-    git clone --depth 1 --single-branch -q "$PBB_GIT" "$PBB_TEMP_DIR" \
-      && msg_yay "Cloned $PBB_GIT"
+    git clone --depth 1 --single-branch -q "$PBB_GIT" "$PBB_TEMP_DIR"
+    msg_yay "Cloned $PBB_GIT"
   else
     msg_run "Starting to update $PBB_GIT"
     git -C "$PBB_TEMP_DIR" reset --hard origin/master
-    git -C "$PBB_TEMP_DIR" pull -q \
-      && msgr yay "Updated $PBB_GIT"
+    git -C "$PBB_TEMP_DIR" pull -q
+    msg_yay "Updated $PBB_GIT"
   fi
+  return 0
 }
 
+# Get the cheat destination directory for pure-bash-bible
 prepare_cheat_dest()
 {
   local cheat_dest
   cheat_dest="$(cheat -d | grep pure-bash-bible | head -1 | awk '{print $2}')"
 
-  if [ ! -d "$cheat_dest" ]; then
+  if [[ ! -d "$cheat_dest" ]]; then
     mkdir -p "$cheat_dest"
   fi
 
   echo "$cheat_dest"
+  return 0
 }
 
 # Processes chapter files from the pure-bash-bible repository and generates or updates corresponding cheat sheets.
@@ -83,19 +89,22 @@ process_chapters()
     LC_ALL=C perl -pi.bak -e 's/\<\!-- CHAPTER END --\>//' "$cheat_file"
     rm "$cheat_file.bak"
 
-    if [ '---' != "$(head -1 < "$cheat_file")" ]; then
+    if [[ '---' != "$(head -1 < "$cheat_file")" ]]; then
       local metadata
       metadata="$PBB_SYNTAX\n$PBB_TAGS\n$PBB_SOURCE\n"
       printf '%s\n%b%s\n%s' "---" "$metadata" "---" "$(cat "$cheat_file")" > "$cheat_file"
     fi
   done
+  return 0
 }
 
+# Install pure-bash-bible cheatsheets
 main()
 {
   check_required_tools
   clone_or_update_repo
   process_chapters
+  return 0
 }
 
 main "$@"