chore: update file headers to new style

.gitattributes

@@ -1,11 +1,15 @@
-# -*- mode: sh; -*-
+# Repository-specific file attribute associations for git.
+#
+# Copyright 2024 California Institute of Technology.
+# License: Modified BSD 3-clause – see file "LICENSE" in the project website.
+# Website: https://github.com/caltechlibrary/template
 
-# Set the default behavior, in case people don't have core.autocrlf set.
+# Default interpretation of files, in case people don't have core.autocrlf set.
 # .............................................................................
 
 * text=auto
 
-# Specify what's text and should be normalized.
+# Common text files that should be normalized.
 # .............................................................................
 
 *.py text
@@ -18,19 +22,17 @@
 *.bat text
 *.sh text
 LICENSE text
-CONTRIBUTING text
 
-# Denote all files that are truly binary and should not be modified.
+# Common files that are truly binary and should not be modified.
 # .............................................................................
 
 *.png binary
 *.jpg binary
 *.xls binary
 *.doc binary
 
-# This next one is because in other projects, we've had problems with git
-# getting confused about line endings when people using Windows and Mac edit
-# the same files.
+# Special case for CSV. We've had problems with git getting confused about
+# CSV line endings when both Windows & Mac users edited the same files.
 # .............................................................................
 
 *.csv binary diff=csv

.gitignore

@@ -1,16 +1,17 @@
-# @file    .gitignore
-# @brief   Rules for files and subdirectories to be ignored by git
-# @license Please see the file named LICENSE in the project directory
-# @repo    https://github.com/caltechlibrary/template
+# Rules for files and subdirectories to be ignored by git.
+#
+# Copyright 2024 California Institute of Technology.
+# License: Modified BSD 3-clause – see file "LICENSE" in the project website.
+# Website: https://github.com/caltechlibrary/template
 #
 # ╭─────────────────────── Notice ── Notice ── Notice ────────────────────────╮
 # │ The recommended approach is to add ONLY project-specific rules to the     │
 # │ .gitignore of a repo. Users can put rules that apply to their individual  │
 # │ ways of doing things into global git ignore files that they set up using  │
-# │ (e.g.) "git config --global core.excludesfile ~/.gitignore_global".       │
-# │ A number of files such as Emacs checkpoint and backup files are things    │
-# │ that are not specific to a given project; rather, Emacs creates them      │
-# │ everywhere, in all projects, because they're a byproduct of how Emacs     │
+# │ (e.g.) "git config --global core.excludesfile ~/.gitignore_global". For   │
+# │ example, a number of files such as Emacs checkpoint and backup files are  │
+# │ things that are not specific to a given project; rather, Emacs creates    │
+# │ them everywhere, in all projects, because they're a byproduct of how it   │
 # │ works. Thus, rules to ignore them belong in users' own global .gitignore  │
 # │ files, not in a project's .gitignore.                                     │
 # │                                                                           │