fix(visualsign): render number fields as amount_v2 (VSP has no number type)

[prasanna-anchorage]

Problem

The Anchorage wallet's Visual Signing Protocol engine has no number field type — its FieldType decoder recognizes only text_v2, address_v2, amount_v2, preview_layout, delta, highlight, rule, accordion, diagnostic. Any field emitted by create_number_field (compute_budget, system, token_2022, jupiter_swap, …) therefore decodes to .unknown and is surfaced as an unsupported field, also flagging its enclosing preview_layout as containsUnsupportedNestedFields.

Fix

Render the Number variant as text_v2 at the serialization layer (serialize_to_map/get_expected_fields), carrying the human value (incl. any unit) from fallback_text. The in-memory SignablePayloadField::Number variant and the create_number_field helper are unchanged — callers and variant-matching tests keep working; only the wire output changes. They stay visibly distinct from amount_v2 (these are not amounts).

General fix, independent of the DFlow render work.

Tests

cargo test -p visualsign -p visualsign-solana, clippy --all-targets -D warnings, cargo fmt --check pass. The one serialization-output assertion in jupiter_swap (Slippage field type) updated number → text_v2.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR updates the Visual Signing Protocol JSON wire output so that SignablePayloadField::Number no longer serializes as a number field type (unsupported by Anchorage), and instead serializes as text_v2 while preserving the human-readable display value via fallback_text. This keeps the in-memory Rust enum variant unchanged while making emitted payloads compatible with the Anchorage wallet decoder.

Changes:

• Serialize SignablePayloadField::Number as Type: "text_v2" and emit a TextV2 payload derived from common.fallback_text.
• Update get_expected_fields so serialization verification expects TextV2 for the Number variant.
• Adjust the Jupiter Swap serialization assertion to expect text_v2 on the wire for the Slippage field.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/visualsign/src/lib.rs	Changes Number serialization to emit text_v2 + TextV2 using fallback_text, and updates expected-field verification accordingly.
src/chain_parsers/visualsign-solana/src/presets/jupiter_swap/mod.rs	Updates the JSON serialization test expectation for the Slippage field from number to text_v2.

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[prasanna-anchorage]

Updated per the VSP design: there is no number field type (HSM vsp.py + iOS decoder list text_v2/address_v2/amount_v2/preview_layout/list_layout/delta/accordion/diagnostic/divider). So number now serializes as amount_v2 (amount = value, abbreviation = unit; unitless = empty abbreviation, which iOS parseAmount accepts). In-memory Number variant + create_number_field unchanged; only the wire output. Force-pushed (SSH-signed).

(Branch name fix/number-fields-text-v2 is legacy from the earlier text_v2 approach.)

[prasanna-anchorage]

Superseded by #393 — same change, renamed branch fix/number-fields-amount-v2 to match the amount_v2 content (this branch was the legacy text-v2 name).