Add the local project, framework submodule, hooks and templates

After the repositories and the mirror, the script now creates the local
project: the directory, git on main, credential-free origin (and github)
remotes, and the license history from Gitea. Then it adds the framework as
a submodule over SSH, installs its skills and git hooks once (plan gate
optional), and copies the AGENTS.md and artifact registry templates.

Nothing is overwritten without a yes: an existing directory, core.hooksPath,
AGENTS.md or docs/artifact-registry.md each ask first (default no). Without
SSH the framework steps can only be skipped, after a yes. No commit is made
in the new project. New optional config key FRAMEWORK_REPO.

New library files git.sh, localproject.sh and framework.sh. Tests run real
git against local bare repositories that stand in for Gitea and the
framework, with a private git configuration (769 checks). The README is now
the full guide.

Task: MIL-003#1
Task: MIL-003#2
Task: MIL-003#3
Task: MIL-003#4
Task: MIL-003#5
Refs #15
Refs #16
Refs #17
Refs #18
Refs #19

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/lib/config.sh

@@ -100,6 +100,9 @@ validate_config() {
   CONFIG[MIRROR_INTERVAL]="${CONFIG[MIRROR_INTERVAL]:-$DEFAULT_MIRROR_INTERVAL}"
   is_valid_interval "${CONFIG[MIRROR_INTERVAL]}" ||
     die "MIRROR_INTERVAL in $CONFIG_FILE must look like 10m0s or 8h0m0s"
+  CONFIG[FRAMEWORK_REPO]="${CONFIG[FRAMEWORK_REPO]:-$DEFAULT_FRAMEWORK_REPO}"
+  is_valid_framework_repo "${CONFIG[FRAMEWORK_REPO]}" ||
+    die "FRAMEWORK_REPO in $CONFIG_FILE must look like OWNER/NAME"
 }
 
 validate_credentials() {