fix: drop gclient from default cargo sails new dev-deps

[ukint-vs]

Summary

• Drop gclient from the default dev-dep feature list in cargo sails new-scaffolded projects (rs/cli/src/program_new.rs).
• Add an opt-in note in the scaffold README pointing builders at cargo add sails-rs --dev --features gclient for live-node tests.
• Update rs/cli/README.md to match.

Context

Issue #1334 (Issue 1) reports that fresh-scaffold builds drag in a heavy substrate / subxt / sp-core / jsonrpsee tree via gclient, which the default tests do not use. The reporter's specific resolution-failure claim (subxt 0.44.0 doesn't exist) was inaccurate — subxt 0.44.0–0.44.3 have been published since 2025-08-29 and resolve cleanly today — but the underlying complaint about scaffold weight and surface area for misdiagnosis is legitimate.

The default tests/gtest.askama only uses GtestEnv and DEFAULT_USER_ALICE from sails_rs::gtest. There is no gclient reference anywhere in the generated project. gclient is dead weight unless the builder later writes off-chain RPC tests against a live node.

Impact

Measured on a freshly scaffolded cargo sails new sails-fix-check:

metric	before	after	delta
Cargo.lock packages	818	697	−121
Cargo.lock lines	8928	7405	−1523
cargo tree references to gclient/subxt/gsdk	many	0	—

Test plan

• cargo build -p sails-cli --release
• cargo clippy -p sails-cli --all-targets --locked -- -D warnings (clean)
• cargo sails new <name> and confirm scaffolded [dev-dependencies] sails-rs shows features = ["gtest"] only
• cargo tree on the scaffolded project shows no gclient / subxt / gsdk
• Generated README contains the gclient opt-in note
• CI green

Out of scope

This PR addresses Issue 1 from #1334 only. Issues 2 (ReflectHash boilerplate) and 3 (msg::source import) are tracked separately. There is also an unrelated StateMut/Infallible build failure on master from a version skew between the published sails-rs 1.0.0-beta.4 prelude and the post-#1331 master prelude — not addressed here.

Refs #1334

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request makes the gclient dependency optional for integration tests by removing it from the default development dependencies in the program generator. It also updates the CLI documentation and the generated project README template with instructions on how to manually enable gclient for live-node testing. I have no feedback to provide as there were no review comments.