Add comprehensive chezmoi notes with modern templating best practices

[Copilot]

Created chezmoi documentation covering 10+ modern best practices based on current chezmoi docs, plus updated outdated chezmoi references in docker.md.

New: content/notes/development/tooling/chezmoi.md

• Template syntax: Whitespace control with {{- and -}}
• OS detection: .chezmoi.os, .chezmoi.osRelease.id, WSL detection, chassis type
• Reusable templates: .chezmoitemplates/ with TOML data injection
• Secret management: 1Password (onepasswordRead) and Bitwarden integration
• External dependencies: .chezmoiexternal.toml for oh-my-zsh, vim-plug, GitHub releases
• Conditional ignoring: Templated .chezmoiignore patterns
• Init prompts: promptStringOnce, promptChoiceOnce, promptBoolOnce
• Age encryption: Key generation, passphrase protection, auto-decrypt scripts
• Run scripts: run_once_, run_onchange_, run_before_/run_after_, daily/weekly scheduling
• Debugging: chezmoi data, chezmoi execute-template

Example pattern for OS-specific config:

{{- $osid := .chezmoi.os -}}
{{- if hasKey .chezmoi.osRelease "id" -}}
{{-   $osid = printf "%s-%s" .chezmoi.os .chezmoi.osRelease.id -}}
{{- end -}}

{{ if eq .osid "linux-debian" }}
# Debian-specific configuration
{{ end }}

Updated: content/notes/development/tooling/docker.md

• Replaced deprecated git.io/chezmoi with get.chezmoi.io
• Added proper shell code blocks
• Cross-linked to new chezmoi notes

Original prompt

Consider current chezmoi templating against chezmoi docs (context7) and make 10 improvements without regression to leverage chezmoi correctly.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.