streams: per-invocation channel, pumping mode, filter pipeline wiring

exec: LineChannel bounded ring (cap=16) with abort/eof/marker fields.
Shell 'pumping mode' assembles canonical lines from its queue into the
channel while the command runs; ^C marks the channel aborted.

Shell-side grammar: USE/TIL pre-drain into the channel before spawn;
<cmd> <path> TIL <marker> sugar drains paths until the marker line.
Interactive TIL: pump_key checks each submitted line against the marker
and closes the channel when it matches.

Exports callbacks run in the command task but touch shell-owned state:
this is safe by construction — the shell blocks in exec_external until
the command completes.  put_line feeds Pipeline::line directly;
get_line pops from the channel (yield-poll when empty).

load: drop NX from image mapping (single-privilege kernel, NX bit 63
reserved when EFER.NXE is set by OVMF); compute image span from section
RVAs not file size.

bins/count: gate binary — reads lines via get_line, reports count via
put_line.  Verified: count USE file → 6; count <path> TIL END → 2;
interactive count TIL DONE → 3; -h filter across task boundary;
^C abort.

v1 stream exports: put_line → Pipeline, get_line ← channel, log_line
→ klog append, exit → abort_current.

Accounting: print_one_line → pipe.line() returns false (head kill /
pager ^C) → the binary should wrap up promptly; accepted: binary does
not check the return value in v1 (phase 3 simplification).

1 files changed, 2 insertions, 1 deletions

diff --git a/rsapi/src/lib.rs b/rsapi/src/lib.rs
index f71e69f..d7b69a2 100644
--- a/rsapi/src/lib.rs
+++ b/rsapi/src/lib.rs
@@ -20,7 +20,8 @@ pub const ABI_VERSION: u32 = 1;
 /// Entry-point signature.  `extern "C"` on the x86_64-unknown-uefi
 /// target is the Win64 convention: the three arguments arrive in
 /// RCX/RDX/R8 on both sides of the table.
-pub type EntryPoint = extern "C" fn(exports: &'static Exports, argc: usize, argv: *const Arg) -> i32;
+pub type EntryPoint =
+    extern "C" fn(exports: &'static Exports, argc: usize, argv: *const Arg) -> i32;
 
 /// One C-style argv element: pointer + length (rs-dos strings are not
 /// NUL-terminated in memory).