refactor(polkavm): isolate optional host composition

[replghost]

Summary

• replace truapi-pvm-host with the optional truapi-polkavm-host 0.2.0 composition crate
• pin polkavm-host-runtime 0.2.0 at 30770959f66db81d46163f70f72f83f1a5507f6d
• keep truapi-server completely independent of PolkaVM
• remove host-core-owned browser exports and generated PolkaVM mobile bindings; UserAgentKit owns those distribution artifacts
• restore the base Android ABI matrix, including armeabi-v7a

Boundary

truapi-polkavm-host is an rlib-only composition dependency. It explicitly exposes the namespaced polkavm_host_runtime and truapi_server APIs plus pinned version/revision constants. Downstream distribution crates decide which native ABI surfaces to export.

Verification

• cargo test -p truapi-polkavm-host --locked
• cargo clippy -p truapi-polkavm-host --all-targets --locked -- -D warnings
• cargo fmt --all -- --check
• cargo tree -p truapi-server --locked contains no PolkaVM dependency

[replghost]

@pgherveou @eugypalu all required checks are green, including Rust/Clippy, Android, iOS, browser artifacts, and license policy. Could one of you provide the required host-sdk-team approval so the merge queue can admit this dependency?

[pgherveou]

can we remove the generated files in the new js packages. Can't these be built from the src files ?

for the new bindings we can also added then to .gitattributes with linguist-generated=true, so that at least they show up as generated artifacts in the code review

[replghost]

Addressed in b0e178e: removed the committed browser dist/ tree, ignored it, and kept build/test/release generation source-driven. npm test now proves a clean package checkout builds the WASM and split workers before checksum verification; npm pack --dry-run --json still contains all ten release files. Added linguist-generated=true for the new Swift and FFI binding outputs in .gitattributes.

[replghost]

Cleanup CI is fully green; ready for rereview and merge queue admission.

[pgherveou]

DQ: why do all these things need to live in host-rust-core, they don't seem to have dependency on the rust-core stuff, and could be shipped independently ?

[replghost]

They share the Rust core directly rather than only co-locating artifacts:

• @parity/pvm-browser-runtime compiles rust/crates/pvm-runtime to wasm32-unknown-unknown; its JS workers are the adapter around that Wasm ABI.
• The same pvm-runtime crate is linked into truapi-server, so the existing UniFFI cdylib/XCFramework/AAR exports the native Swift/Kotlin runtime. A separate repository would require a second native library and package lifecycle in every host.
• pvm-gpu-wire is shared by the native and browser implementations, keeping bounds and binary GPU records identical.
• The existing host-rust-core CI/release jobs already regenerate UniFFI and publish the browser/native artifacts from one reviewed commit.

They could be split, but that would duplicate the Rust source/pins and create independent browser, XCFramework, and AAR versioning with an ABI-drift boundary. Keeping the runtime here makes the host-neutral Rust implementation the single source for all three targets; Epoca/Dotli/Brevity/Desktop remain independent consumers.

[replghost]

Does that shared Rust/UniFFI dependency path resolve the repository-placement concern, or do you want the runtime split into a separate repository before merge?

[replghost]

Additional review completed. Fixed three concrete boundary issues:

• Native constructors now enforce the same program, gas, asset-count, per-file, aggregate-byte, and safe-path limits as the browser ABI before guest compilation.
• The browser compiler backend now enforces the manifest graphics profile, one Tri2D submission per update, CoreVM framebuffer-only behavior, and GPU state/sequence errors consistently with the interpreter.
• Browser worker termination now closes its timer and MessageChannel ports; invalid launches no longer leak host-thread channels.

Added behavioral browser tests for malformed launch inputs and cross-profile framebuffer submission. Full workspace result: 1,205 tests passed, Clippy -D warnings passed, package tests 4/4 passed, and committed iOS bindings remain current.

Vendored commit 56c67a306fc276129829f94db85a622061e17882 into both consumers and exercised it end to end: Epoca App v2 10/10 plus seven-app browser matrix 45/45; Dotli Doom, Quake, Duke3D, NES, egui, GPU Cube, and Scene Lab all passed on the compiler backend.

[replghost]

PolkaVM dependency update:

• Rebased epoca/aarch64-jit-0.37 onto current paritytech/polkavm@master; branch head is e06cce9, 6 commits ahead / 0 behind.
• Ported the AArch64 JIT across the current code-blob, 32-bit address, dynamic-paging, memset, and 16 KiB page semantics.
• PolkaVM verification: 4,090 passed, 2 ignored; AArch64 assembler clippy passes with warnings denied.
• This PR now pins e06cce9 in commit 23f50c64.
• Host CI is green, including Rust workspace, native build, iOS bindings/package, browser provider, codegen, and dependency licenses.