feat(composer): bake the dev build warning deadline in at build time

Composer defines COMPOSER_DEV_WARNING_TIME from its phar stub when the
compiled version is a commit hash rather than a tag, so the value exists
only in the build artifact. It was a todo!() in the PHP shim, leaving the
warning branch in Application::do_run unreachable.

A build script now derives it the way Compiler does, from git describe
and the HEAD commit date, and composer::COMPOSER_DEV_WARNING_TIME holds
the result as a Rust constant instead of a runtime-defined one.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/crates/shirabe/src/composer.rs b/crates/shirabe/src/composer.rs
index 356aefc1..fca19539 100644
--- a/crates/shirabe/src/composer.rs
+++ b/crates/shirabe/src/composer.rs
@@ -21,6 +21,16 @@ pub const RELEASE_DATE: &str = "2026-04-14 13:31:52";
 pub const SOURCE_VERSION: &str = "";
 pub const RUNTIME_API_VERSION: &str = "2.2.2";
 
+/// The deadline after which a development build reports itself as outdated, or `None` for a build
+/// made from a tagged revision. Baked in by `build.rs`.
+///
+/// Composer declares this as the global constant COMPOSER_DEV_WARNING_TIME from its phar stub, so
+/// a plugin can read it back with `defined()`/`constant()`. Here it is a Rust constant, and
+/// plugins cannot observe it. Technically speaking, it is incompatible with Composer, but trivial
+/// enough.
+pub const COMPOSER_DEV_WARNING_TIME: Option<i64> =
+    include!(concat!(env!("OUT_DIR"), "/dev_warning_time.rs"));
+
 pub fn get_version() -> String {
     if VERSION == "@package_version@" {
         return SOURCE_VERSION.to_string();