feat(stdlib): namespaced standard library (issue #2)

Implement the bulk of the namespaced-stdlib proposal (workshopsoft/ludic#2):
156 namespace methods across Math, Text, List, Ease, Collide, World, Net,
Sys, Save, Mem, extended Screen, Color functions, extended Random, and Time.
All deterministic fixed-point; self-hosting (C-free bootstrap fixpoint holds).

Compiler (selfhost/):
- Math.*: sqrt/sin/cos/tan/atan2/asin/acos (fixed-point runtime prelude —
  bit-by-bit isqrt, 256-entry interpolated sine table, Ross atan2), plus
  hypot/dist/dist2/deg_to_rad/rad_to_deg/posmod/wrap/ping_pong/snapped/
  move_toward/smoothstep/lerp/remap/sign/floor/ceil/round.
- Text.* (complete): upper/lower/trim/repeat/pad, split/join/replace,
  and the libc-backed queries.
- List.* (complete): insert/remove_at/remove/sort plus the earlier ops.
- Ease.* (in/out/in_out/back/bounce) and Collide.* (rects/point_rect/
  circles/rect_circle).
- Phase 3: World/Net/Sys/Save namespaced over the bare builtins (byte-
  identical IR) and Mem.* (bytes/words/copy/fill/peek/poke).
- Screen.* extended (line/circle/fill_circle/triangle/fill_triangle via new
  runtime primitives; sprite/sprite_scaled aliases), Color.* functions,
  Random.* (value/int/sign), Time.* (frame/delta/elapsed/now — new
  game-loop frame counter).
- Fix a lexer bug: fixed-point literals with >4 fractional digits overflowed.

Docs & tooling:
- 129 new per-symbol doc pages; gen.py made data-driven (namespaces
  discovered from the docs, no hardcoded list); new check-impl.py enforces
  that every implemented namespace method / keyword / type / phase has a
  doc page, wired into `x test-tools`. Document the previously-undocumented
  keywords (break/continue/where/entry/new/public + and/or/not tokens).
- LSP: namespaced signature help (ns_method_sig) covering every namespace.

Tests: 12 new self-host/regression tests + a golden render for the drawing
primitives. All suites green (selfhost 21, regression 45, tools 29).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/language/sys/_section.md

@@ -0,0 +1,7 @@
+---
+id: sys
+title: Sys
+order: 6
+---
+
+Process and OS access — command-line arguments, environment, exit code, running a shell command, and raw file I/O. Outside the deterministic simulation.

docs/language/sys/sys-arg.md

@@ -0,0 +1,14 @@
+---
+id: sys-arg
+name: Sys.arg
+category: sys
+kind: namespace-method
+tokens: Sys.arg
+sig: Sys.arg(i) -> str
+tip: A command-line argument by index.
+order: 0
+ns: Sys
+member: arg
+---
+
+Returns the <code>i</code>-th command-line argument; index 0 is the program path.

docs/language/sys/sys-arg_count.md

@@ -0,0 +1,14 @@
+---
+id: sys-arg_count
+name: Sys.arg_count
+category: sys
+kind: namespace-method
+tokens: Sys.arg_count
+sig: Sys.arg_count() -> int
+tip: The number of command-line arguments.
+order: 1
+ns: Sys
+member: arg_count
+---
+
+Returns how many command-line arguments were passed, including the program path.

docs/language/sys/sys-env.md

@@ -0,0 +1,14 @@
+---
+id: sys-env
+name: Sys.env
+category: sys
+kind: namespace-method
+tokens: Sys.env
+sig: Sys.env(name) -> str
+tip: Read an environment variable.
+order: 4
+ns: Sys
+member: env
+---
+
+Returns the value of environment variable <code>name</code>, or a null string if it is unset.

docs/language/sys/sys-exit.md

@@ -0,0 +1,14 @@
+---
+id: sys-exit
+name: Sys.exit
+category: sys
+kind: namespace-method
+tokens: Sys.exit
+sig: Sys.exit(code) -> void
+tip: End the process with a status code.
+order: 2
+ns: Sys
+member: exit
+---
+
+Terminates the program immediately, returning <code>code</code> to the shell.

docs/language/sys/sys-file_close.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_close
+name: Sys.file_close
+category: sys
+kind: namespace-method
+tokens: Sys.file_close
+sig: Sys.file_close(file) -> void
+tip: Close a file.
+order: 11
+ns: Sys
+member: file_close
+---
+
+Closes <code>file</code>, flushing any buffered writes.

docs/language/sys/sys-file_open.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_open
+name: Sys.file_open
+category: sys
+kind: namespace-method
+tokens: Sys.file_open
+sig: Sys.file_open(path, mode) -> ptr
+tip: Open a file.
+order: 6
+ns: Sys
+member: file_open
+---
+
+Opens <code>path</code> with the given <code>mode</code> (as C <code>fopen</code>) and returns a file handle, or null on failure.

docs/language/sys/sys-file_read.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_read
+name: Sys.file_read
+category: sys
+kind: namespace-method
+tokens: Sys.file_read
+sig: Sys.file_read(file, buf, n) -> int
+tip: Read bytes from a file.
+order: 7
+ns: Sys
+member: file_read
+---
+
+Reads up to <code>n</code> bytes from <code>file</code> into <code>buf</code> and returns the number read.

docs/language/sys/sys-file_seek.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_seek
+name: Sys.file_seek
+category: sys
+kind: namespace-method
+tokens: Sys.file_seek
+sig: Sys.file_seek(file, offset, whence) -> int
+tip: Move a file's read/write position.
+order: 9
+ns: Sys
+member: file_seek
+---
+
+Seeks <code>file</code> to <code>offset</code> relative to <code>whence</code> (as C <code>fseek</code>).

docs/language/sys/sys-file_tell.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_tell
+name: Sys.file_tell
+category: sys
+kind: namespace-method
+tokens: Sys.file_tell
+sig: Sys.file_tell(file) -> int
+tip: The current file position.
+order: 10
+ns: Sys
+member: file_tell
+---
+
+Returns the current read/write offset of <code>file</code>.

docs/language/sys/sys-file_write.md

@@ -0,0 +1,14 @@
+---
+id: sys-file_write
+name: Sys.file_write
+category: sys
+kind: namespace-method
+tokens: Sys.file_write
+sig: Sys.file_write(file, buf, n) -> int
+tip: Write bytes to a file.
+order: 8
+ns: Sys
+member: file_write
+---
+
+Writes <code>n</code> bytes from <code>buf</code> to <code>file</code> and returns the number written.

docs/language/sys/sys-read_char.md

@@ -0,0 +1,14 @@
+---
+id: sys-read_char
+name: Sys.read_char
+category: sys
+kind: namespace-method
+tokens: Sys.read_char
+sig: Sys.read_char() -> int
+tip: Read one byte from standard input.
+order: 5
+ns: Sys
+member: read_char
+---
+
+Reads and returns the next byte from standard input, or a negative value at end of input.

docs/language/sys/sys-run.md

@@ -0,0 +1,14 @@
+---
+id: sys-run
+name: Sys.run
+category: sys
+kind: namespace-method
+tokens: Sys.run
+sig: Sys.run(command) -> int
+tip: Run a shell command.
+order: 3
+ns: Sys
+member: run
+---
+
+Runs <code>command</code> through the system shell and returns its exit status. Blocks until it finishes.

docs/language/sys/sys-stderr.md

@@ -0,0 +1,14 @@
+---
+id: sys-stderr
+name: Sys.stderr
+category: sys
+kind: namespace-method
+tokens: Sys.stderr
+sig: Sys.stderr() -> ptr
+tip: The standard error handle.
+order: 13
+ns: Sys
+member: stderr
+---
+
+Returns the standard-error file handle, for <code>Sys.file_write</code>.

docs/language/sys/sys-stdout.md

@@ -0,0 +1,14 @@
+---
+id: sys-stdout
+name: Sys.stdout
+category: sys
+kind: namespace-method
+tokens: Sys.stdout
+sig: Sys.stdout() -> ptr
+tip: The standard output handle.
+order: 12
+ns: Sys
+member: stdout
+---
+
+Returns the standard-output file handle, for <code>Sys.file_write</code>.