feat(cli): install in one command, and call the CLI ludic

Getting started meant cloning the repository, bootstrapping a compiler and
learning a task runner called `x`. That is a contributor's workflow handed to
everyone who wants to try the language.

Installing is now one command:

    curl -fsSL https://workshopsoft.pages.workshopsoft.io/ludic/install.sh | sh

install.sh puts a complete toolchain — compiler, CLI, engine runtime, bundled
ludic.* packages, formatter, language server — in ~/.ludic and adds it to PATH.
Prebuilt artifacts are checksum-verified; where a platform has none, or the
release predates this layout, it bootstraps from the compiler's own IR seed with
clang. The docs site publishes the script beside the pages that quote it, so the
page and the script can never come from different releases.

`x` becomes `ludic`, and the surface splits by audience. A user of the language
sees `new`, `run`, `build`, `test`, `add`, `fmt`, `lsp`, `doctor`, `upgrade`;
`ludic new` scaffolds a project that builds and plays as it stands. Everything
the toolchain repo needs moved under `ludic dev` — build, test, reseed,
bootstrap-cfree, docs-gen, release — unchanged apart from the namespace. Those
tasks read arguments one position further along, so dispatch_dev sets a shift
and commands use arg_n()/arg_total() rather than each knowing its own depth.

Release artifacts become complete install roots (bin/ beside runtime/, packages/
and VERSION) rather than bare binaries, which is what the installer unpacks.
`ludic dev test` asserts the whole shape: it stages an install, puts it on PATH
with no LUDIC_HOME, and runs new -> build -> test through it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

examples/README.md

@@ -1,14 +1,14 @@
 # Examples
 
 A curated tour of Ludic, grouped by intent. Every example here is exercised by
-the test suite (`bin/x test` / `bin/x selfhost-test`), so nothing in this
+the test suite (`bin/ludic dev test` / `bin/ludic dev selfhost-test`), so nothing in this
 directory silently rots.
 
 Run any program straight from the repository root (so `assets/` resolves):
 
 ```sh
-bin/x app examples/games/snake.ludic              # compile + open a real window
-bin/x app examples/games/snake.ludic --headless   # render one frame to build/out.ppm
+bin/ludic build examples/games/snake.ludic              # compile + open a real window
+bin/ludic build examples/games/snake.ludic --headless   # render one frame to build/out.ppm
 bin/ludic examples/lang/offline_rewards.ludic     # compile + run a plain program
 ```
 

examples/games/snake.ludic

@@ -1,6 +1,6 @@
 # ============================================================================
 # snake.ludic — a small, complete game in Ludic. No sprites or assets: every
-# pixel is drawn from primitives. Build: bin/x app examples/games/snake.ludic
+# pixel is drawn from primitives. Build: bin/ludic build examples/games/snake.ludic
 #
 # It shows the everyday shape of a Ludic game: an ECS for the moving parts (one
 # entity per snake segment), named program state for the rest, and a Render

examples/lang/detach.ludic

@@ -11,7 +11,7 @@
 #   25   @OnDetach(Shield): reads the outgoing amount 5, prints 5 + 20
 #   0    the Shield is gone — nothing matches
 #
-#   bin/x game-build bin/ludicc examples/lang/detach.ludic /tmp/detach
+#   bin/ludic dev game-build bin/ludicc examples/lang/detach.ludic /tmp/detach
 #   /tmp/detach </dev/null
 program Detach {
   property Tag    { v: int = 0 }

examples/lang/reason.ludic

@@ -9,7 +9,7 @@
 #   503    Enemy A despawned in-world (Despawned): drop its loot, 3 + 500
 #   1009   Enemy B outlived the run; at quit (Quit) it skips loot, 9 + 1000
 #
-#   bin/x game-build bin/ludicc examples/lang/reason.ludic /tmp/reason
+#   bin/ludic dev game-build bin/ludicc examples/lang/reason.ludic /tmp/reason
 #   /tmp/reason </dev/null
 program Reasons {
   property Health { hp: int = 0 }

examples/lang/scenes.ludic

@@ -12,7 +12,7 @@
 #     201 900  frame 3: Play.World.Step, then Hud.Draw
 #     202 900  frame 4: Step reaches 2 -> quit(); Hud.Draw paints the last frame
 #
-#   bin/x game-build bin/ludicc examples/lang/scenes.ludic /tmp/scenes
+#   bin/ludic dev game-build bin/ludicc examples/lang/scenes.ludic /tmp/scenes
 #   printf 'aaaa' | /tmp/scenes
 program SceneDemo {
   var counter: int = 0

examples/library/coverage.ludic

@@ -1,6 +1,6 @@
-# coverage.ludic — a spec built to be measured by `bin/x test --coverage` (issue
+# coverage.ludic — a spec built to be measured by `bin/ludic dev test --coverage` (issue
 # #45). Compiled with `--coverage`, every statement bumps a per-source-line hit
-# counter; at exit the counts are dumped and `bin/x test --coverage` turns them
+# counter; at exit the counts are dumped and `bin/ludic dev test --coverage` turns them
 # into a per-file line-coverage report.
 #
 # The tests below exercise `sign` fully but only the taken branches of `grade`,

examples/networking/net_demo.ludic

@@ -14,7 +14,7 @@
 #   5. rt_receive()              — the client reconciles to the authoritative x=5
 #
 # Prints 5 / 999 / 5. Build & run with the Ludic toolchain only:
-#   bin/x app examples/networking/net_demo.ludic --headless && ./build/net_demo_headless
+#   bin/ludic build examples/networking/net_demo.ludic --headless && ./build/net_demo_headless
 import "net_rt.ludic"
 
 program NetDemo {