feat(admin subscription): add page subscription and tabs

[alireza013013]

Description

• implement admin subscription plan management API composable and types
• add another types for input post,put useApiService for handle object in object or list
• add admin subscription feature management functionality and handle api in composable
• add admin subscription price management functionality in composable
• add admin subscription gateway mapping functionality in composable
• remove getItemById from feature,gateway,price
• add page subscription
• add tabs for price,plan,gatway,feature
• complete plan tab and get data show in table
• add modal for add and detail and delete plan
• complete feature tab and get data show in table
• add modal for add and detail and delete feature
• add feature management for admin subscription plans by adding feature modal
• complete price tab and get data show in table
• add modal for add and detail and delete price
• add modal for add and detail and delete gateway

Type of Change

• Bug fix
• New feature
• Documentation update
• Other (please describe):

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings/errors
• I have added tests that prove my fix is effective or that my feature works

[vercel]

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[sanaderi]

Review

Good adherence to the project's existing composable/CRUD conventions structurally, but there's a real correctness bug that should be fixed before merge, plus a nav placement note.

Bugs to fix before merge

Module-level singleton state in all four new composables — cross-tab data corruption

In every composables/api/subscription/*.api.ts file, several ref()s are declared outside the exported function (module scope), making them shared singletons across every call site for the app's entire lifetime, instead of being scoped per composable instance:

• useSubscriptionFeatureAdmin.api.ts — data, featureOptions, totalCount, pageCount, and all loading flags are module-level.
• useSubscriptionPlanAdmin.api.ts — totalCount, pageCount, planFeatures, and loading flags are module-level (only data/loadingGetData are correctly scoped per-call, inconsistently with the rest).
• Same pattern in the price and gateway-mapping composables.

This isn't theoretical — it's concretely triggered by this PR's own code, because all four tabs mount at once (Vuetify's v-window renders every v-window-item up front, not lazily):

• prices/form.vue calls useSubscriptionPlanAdmin().getPlans({ page: 1, pageSize: 1000 }) on mount to populate the "Plan" dropdown when adding/editing a Price. Since totalCount/pageCount are the same refs plans/index.vue's pagination UI reads, opening "Add Price" after visiting the Plans tab will silently corrupt the Plans tab's displayed count and page-count.
• gateway-mappings/form.vue does the identical thing with useSubscriptionPriceAdmin().getPrices({ page: 1, pageSize: 1000 }) to populate its "Price" dropdown — but here data itself is shared too, so opening "Add Gateway Mapping" will overwrite the Prices tab's own paginated table (10/20/50 rows) with up to 1000 rows and recompute its pageCount to 1, visibly breaking the Prices tab.

Fix: move all these refs inside the exported composable function (matching how data/loadingGetData are already scoped correctly in the plan composable — the pattern just needs to be applied consistently everywhere). This also sidesteps the general Nuxt/SSR hazard of module-scoped state being created once per server process rather than per request.

Navigation placement

The new "Subscription" menu item (app/layouts/admin.vue) is currently added under the Caption group (alongside Contact Us, User Management, Tags, Transactions, Payments). Please move it to the General group, next to Settings, instead.

Style / consistency (low severity)

• app/layouts/admin.vue — new menu entry title is 'Subscription ' with a trailing space.
• Detail-fetch strategy is inconsistent: plans/detail.vue re-fetches the item by ID via getItemById on modal open, while features/detail.vue, prices/detail.vue, and gateway-mappings/detail.vue just receive the already-loaded row object as a prop (no extra request). Not wrong, but worth aligning — the plan list already has full data available, so the extra round-trip is avoidable.