Re-port SQLite to the flat platform

Brings SQLite back online under the new flat-platform architecture (it had
been dropped during the zig-compiler migration and only survived as disabled
`.todoroc` examples).

- platform/InternalSqlite.roc, platform/Sqlite.roc: host-ABI types plus the
  full decoder/combinator/lifecycle API (prepare!/bind!/columns!/column_value!/
  step!/reset! + execute!/query!/query_many!/prepared variants, leaf + nullable
  decoders, decode_record/map_value/map_value_result, ErrCode/errcode_to_str).
  The opaque `Stmt :: Box(U64)` handle stores the raw statement pointer.
- src/lib.rs: SQLite host fns over libsqlite3-sys (bundled) using the box-payload
  handle helpers, a per-path connection cache, and value/error marshalling.
- Cargo.toml: add libsqlite3-sys = "=0.33.0" (bundled).
- examples/sqlite-basic.roc, sqlite-everything.roc (+ todos.db / todos2.db
  fixtures): migrated from the old syntax; both run green.
- ci: run sqlite-basic in the expect suite.

Note: the regenerated src/roc_platform_abi.rs requires the upstream RustGlue.roc
box-header fix (decref_box_with now takes an explicit payload_contains_refcounted
flag instead of inferring it from payload_decref.is_some(); the old inference
freed Box(U64) host handles from the wrong base and segfaulted). basic-cli must
be regenerated against a roc that includes that fix.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: lukewilliamboswell

Cargo.lock

@@ -14,6 +14,7 @@ crate-type = ["staticlib"]
 crossterm = "=0.29.0"
 getrandom = "=0.2.16"
 libc = "=0.2.180"
+libsqlite3-sys = { version = "=0.33.0", features = ["bundled"] }
 
 [target.'cfg(not(target_os = "macos"))'.dependencies]
 sys-locale = "=0.3.2"

Cargo.toml

@@ -129,6 +129,7 @@ EXPECT_EXAMPLES=(
     "tty"
     "dir"
     "env-var"
+    "sqlite-basic"
 )
 
 for roc_file in "${EXAMPLES_DIR}"*.roc; do

ci/all_tests.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/expect
+
+# uncomment line below for debugging
+# exp_internal 1
+
+set timeout 7
+
+source ./ci/expect_scripts/shared-code.exp
+
+set env(DB_PATH) ./examples/todos.db
+
+spawn $env(EXAMPLES_DIR)sqlite-basic
+
+
+set expected_output [normalize_output {
+All Todos:
+    id: 3, task: Share my ❤️  for Roc, status: Todo
+
+Completed Todos:
+    id: 1, task: Prepare for AoC, status: Completed
+}]
+
+expect $expected_output {
+    expect eof {
+        check_exit_and_segfault
+    }
+}
+
+puts stderr "\nExpect script failed: output was not as expected. Diff the output with expected_output in this script. Alternatively, uncomment `exp_internal 1` to debug."
+exit 1

ci/expect_scripts/sqlite-basic.exp

@@ -0,0 +1,84 @@
+app [main!] { pf: platform "../platform/main.roc" }
+
+import pf.Env
+import pf.Stdout
+import pf.Sqlite
+
+# To run this example: check the README.md in this folder and set `export DB_PATH=./examples/todos.db`
+
+# Demo of basic Sqlite usage
+
+# Sql to create the table:
+# CREATE TABLE todos (
+#     id INTEGER PRIMARY KEY AUTOINCREMENT,
+#     task TEXT NOT NULL,
+#     status TEXT NOT NULL
+# );
+
+main! = |_args| {
+    db_path =
+        match Env.var!("DB_PATH") {
+            Ok(p) => p
+            Err(_) => "./examples/todos.db"
+        }
+
+    todos = query_todos_by_status!(db_path, "todo")?
+
+    _h1 = Stdout.line!("All Todos:")
+
+    List.for_each!(todos, |todo| print_todo!(todo))
+
+    completed_todos = query_todos_by_status!(db_path, "completed")?
+
+    _h2 = Stdout.line!("")
+    _h3 = Stdout.line!("Completed Todos:")
+    List.for_each!(completed_todos, |todo| print_todo!(todo))
+
+    Ok({})
+}
+
+Todo : { id : Str, status : TodoStatus, task : Str }
+
+print_todo! = |todo|
+    match Stdout.line!("    id: ${todo.id}, task: ${todo.task}, status: ${status_to_str(todo.status)}") {
+        _ => {}
+    }
+
+query_todos_by_status! = |db_path, status|
+    Sqlite.query_many!(
+        {
+            path: db_path,
+            query: "SELECT id, task, status FROM todos WHERE status = :status;",
+            bindings: [{ name: ":status", value: String(status) }],
+            rows: decode_todo,
+        },
+    )
+
+# A row decoder is `List(Str) -> (Stmt => Try(a, err))`; the new compiler does not
+# support the record-builder (`<-`) sugar, so we combine the leaf decoders by hand.
+decode_todo = |cols|
+    |stmt| {
+        id = Sqlite.i64("id")(cols)(stmt)?
+        task = Sqlite.str("task")(cols)(stmt)?
+        status_str = Sqlite.str("status")(cols)(stmt)?
+        status = decode_todo_status(status_str)?
+        Ok({ id: I64.to_str(id), task, status })
+    }
+
+TodoStatus : [Todo, Completed, InProgress]
+
+status_to_str : TodoStatus -> Str
+status_to_str = |status|
+    match status {
+        Todo => "Todo"
+        Completed => "Completed"
+        InProgress => "InProgress"
+    }
+
+decode_todo_status = |status_str|
+    match status_str {
+        "todo" => Ok(Todo)
+        "completed" => Ok(Completed)
+        "in-progress" => Ok(InProgress)
+        _ => Err(ParseError("Unknown status str: ${status_str}"))
+    }