Update Claude Code plugin skill files for FOCUS 1.3 / 1.4

Problem

The Claude Code plugin's skill files reference outdated FOCUS schema versions and hub-function names. After the FOCUS 1.3 / 1.4 work lands (parent: #2120), the plugin's references become stale and need to be updated so the plugin can correctly guide users on the latest hub schemas.

Affected files

• src/templates/agent-skills/finops-toolkit/references/finops-hubs.md — references schema version and Costs() / Prices() query patterns.
• src/templates/agent-skills/finops-toolkit/references/finops-hubs-deployment.md — currently lists Cost and usage details (FOCUS) - 1.0, 1.0r2.
• src/templates/agent-skills/azure-cost-management/references/azure-cost-exports.md — guidance on FOCUS-format exports.
• src/templates/claude-plugin/agents/ftk-database-query.md — describes the primary Costs table aligned to FOCUS.
• src/templates/claude-plugin/output-styles/ftk-output-style.md — terminology guidance using FOCUS column names.

Required updates

When FOCUS 1.3 / 1.4 support lands, these files should:

1. List the supported FOCUS export dataset versions (including 1.3 and the 1.4 preview).
2. Reference the new hub functions (Costs_v1_3(), Costs_v1_4(), ContractCommitment_v1_3(), etc.) alongside existing ones.
3. Add the new FOCUS 1.3+ columns to the terminology lists (ServiceProviderName, HostProviderName, ContractApplied, allocation columns).
4. Note the ProviderName / PublisherName deprecation (kept in 1.3, removed in 1.4).
5. Mention the new Contract Commitment dataset and its hub function.

Why a separate issue

Plugin updates are decoupled from the core FOCUS 1.4 schema work and can ship after the hub functions stabilize. Tracking it separately keeps the FOCUS 1.4 umbrella focused on schema changes.

Parent: #2120