term: move the term core to subprojects/term

The core now builds, tests, and benchmarks alone, as a Meson subproject
with no dependency on the main tree.

- include/term/ holds term.h and the header-only unicode/. src/ holds
  the core and its private headers. The main tree gets only
  include/term through term_dep, so it cannot reach a private header.
- The term tests, the term benchmarks, the Kitty parser suite, and
  tools/amalgamate.py and tools/generate_unicode.py move with it. The
  tests run as term:<name>.
- The main build passes its -march (arch_flag) and b_ndebug to the
  subproject. A directory configured before this commit needs
  meson configure -Dterm:arch_flag=-march=... once.
- The term tests compile with -UNDEBUG. They do work inside assert.
- The subproject exports term_test_dep with term_api.h, for the main
  tree's render, thumbnail, color, and selection tests.
- The Kitty bridge used struct vector2i and has not compiled since the
  public API redesign. It builds again. 2 of its 14 tests fail: REP
  after a tab, and a cursor report after a resize.
- dirgraph.py drops the term and unicode layers. Its self-test uses pty.
- The symbols test ignores the __odr_asan symbols that ASan adds.

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

1 files changed, 48 insertions, 0 deletions

diff --git a/meson.build b/meson.build
new file mode 100644
index 0000000..a78fa68
--- /dev/null
+++ b/meson.build
@@ -0,0 +1,48 @@
+project('term', 'c',
+  version: '0.1.0',
+  meson_version: '>=1.1.0',
+  default_options: [
+    'c_std=c11',
+    'warning_level=3',
+    'b_ndebug=if-release',
+  ],
+)
+
+cc = meson.get_compiler('c')
+m_dep = cc.find_library('m', required: false)
+if get_option('arch_flag') != ''
+  add_project_arguments(get_option('arch_flag'), language: 'c')
+endif
+
+# A host sees include/ only. The sources also find the public headers
+# without the term/ prefix.
+term_inc = include_directories('include')
+term_private_inc = include_directories('src', 'include/term')
+
+subdir('src')
+
+term_dep = declare_dependency(
+  include_directories: term_inc,
+  link_with: term_headless_lib.get_static_lib(),
+  dependencies: m_dep,
+)
+meson.override_dependency('term', term_dep)
+
+# The private headers too. Only the term tests and benchmarks use it.
+term_internal_dep = declare_dependency(
+  include_directories: [term_inc, term_private_inc],
+  link_with: term_headless_lib.get_static_lib(),
+  dependencies: m_dep,
+)
+
+# The short forms of term.h that the term tests use. A host project can use
+# them in its own tests.
+term_test_dep = declare_dependency(
+  include_directories: include_directories('tests/helpers'),
+  dependencies: term_dep,
+)
+
+if get_option('tests')
+  subdir('tests')
+  subdir('benchmarks')
+endif