refactor(config): parse config values from raw bytes like Zig

Zig parses config values (cli/args.zig, Config.zig field parsers,
config/string.zig) from raw byte slices, and each field type decides
whether it requires UTF-8 (InvalidValue otherwise) or stores bytes. The
port escape-encoded raw bytes into Strings at the line reader and let
fields parse the escaped text, so fields could observe encoding
artifacts; successive audits kept finding such leaks (RV5-RV8).

Field parsers now receive the original bytes: text fields validate UTF-8
where Zig does, byte/path fields store bytes (EncodedOs/OsString). This
resolves all 9 RV8 findings (docs/rewrite/notes/review-rv8-codex.md),
each with a regression test: Windows path conversion fails with
BadPathName instead of substituting U+FFFD; Windows process launch uses
strict UTF-8 like Zig's Command; the WTF-8 decoder accepts paired-
surrogate encodings like Zig; literal U+FDD0 Unicode key triggers;
selection-word-chars and clipboard-codepoint-map reject invalid UTF-8;
font style / codepoint-map family names use original bytes; C title
actions forward bytes; D-Bus new-window/Flatpak conversions match Zig.
Design, sweep and validation: docs/rewrite/notes/final-bytes-refactor.md.

Also moves the bundled iTerm2-Color-Schemes license out of
resources/themes/ so +list-themes no longer lists it as a theme
(output is now byte-identical to Ghostty 1.3.1).

Done by Codex (gpt-6-astra), reviewed and verified by the orchestrator.

Test Plan:
- cargo test --workspace --no-fail-fast (3428 passed, exit 0)
- just check-macos (both), just check-windows, just check-wasm
- +show-config --default --docs, +list-keybinds, +list-actions --docs,
  +list-themes --plain compared with /usr/bin/ghostty

crates/ghostty-lib/src/config_capi.rs

@@ -147,8 +147,8 @@ fn build_backing(value: &CValue) -> Backing {
             for c in cmds {
                 b.strings.push(cstring_value(&c.action_key));
                 b.strings.push(cstring_value(&c.action));
-                b.strings.push(cstring_value(&c.title));
-                b.strings.push(cstring_value(&c.description));
+                b.strings.push(cstring_value(c.title.as_encoded()));
+                b.strings.push(cstring_value(c.description.as_encoded()));
             }
             // The CStrings' heap buffers don't move when the Vec grows.
             b.commands = b
@@ -265,7 +265,7 @@ pub unsafe extern "C" fn ghostty_config_load_file(ptr: ghostty_config_t, path: *
     if let Err(err) = c.config.load_file(&path) {
         log::error!(
             "error loading config from file path={} err={err}",
-            path.as_encoded()
+            path.to_text_lossy()
         );
     }
 }
@@ -511,11 +511,7 @@ pub unsafe extern "C" fn ghostty_config_trigger(
     }
     // SAFETY: `str` points to `len` bytes.
     let s = unsafe { std::slice::from_raw_parts(str.cast::<u8>(), len) };
-    let Ok(s) = std::str::from_utf8(s) else {
-        log::error!("error finding trigger err=InvalidFormat");
-        return default_trigger();
-    };
-    match BindingAction::parse(s) {
+    match BindingAction::parse_bytes(s) {
         Ok(action) => {
             let trigger = c
                 .config