[Feature] AI Credits dashboard: display, labeling, and scale fixes #222

Feature summary

Six display/formatting/scale fixes to the AI Credits dashboard on the GoodData widget (gooddata.gooddollar.org), based on feedback from Hadar Rottenberg (CEO) following the PR #179 production deploy.

Problem or opportunity

Now that the dashboard is live, several labels and values are unclear or imprecise for real users: the top scorecard doesn't show USD or the streaming/subscription breakdown, the flow-rate scorecard is labeled as a daily rate when it should read as a monthly subscription total, the streaming line isn't visible on the G$ Volume chart, the daily table hides sub-cent AI credit usage, and the dashboard defaults to fetching a full year of data unnecessarily.

Proposed solution

1. Rename first scorecard → "Total Credits Bought in G$"; show USD equivalent via weiToUsd(data.global.aiCreditsUsedWei).
2. Add a sub-line: "out of X G$ in subscription (streaming)" via weiToGd(data.global.gdStreamedWei).
3. Rename "G$ Flow Rate" → "Total Monthly Subscriptions", drop the "/day" suffix. New flowRateToMonthly() helper in analyticsConversions.ts:
   const monthlyWei = big * BigInt(2629746) (seconds in a month — plain multiplication, not exponentiation)
4. Make the streaming line visible on the G$ Volume chart — fix/verify LineAreaChart's dual-axis (secondaryYAxis) rendering; fallback to two single-axis charts (one-time deposits vs. streamed) if dual-axis isn't practical.
5. Daily table "AI Credits (USD)" column: .toFixed(2) → .toFixed(3) so sub-cent amounts (e.g. $0.003) show instead of rounding to $0.00.
6. ANALYTICS_DAYS_REQUESTED: 365 → 30 in connector.ts (365-day fetch is a perf hit).

Acceptance criteria

• First scorecard reads "Total Credits Bought in G$" with USD equivalent shown
• Subscription/streaming portion shown as a sub-line under the first scorecard
• Flow-rate scorecard relabeled "Total Monthly Subscriptions", computed via flowRateToMonthly(), no "/day" suffix
• Streaming line visibly rendered on the G$ Volume chart (dual-axis or split charts)
• Daily table AI Credits (USD) column shows 3 decimal places
• Dashboard defaults to a 30-day fetch window

Additional context

PR #179 merged, deployed to production: gooddata.gooddollar.org. Feedback relayed by Thales Barbosa from Hadar Rottenberg (CEO) in #goodbounties-lead, 2026-08-31.

Create the plan (keep this section in the issue body)

Based on the above description create an execution plan in a new sub-issue and preserve the original issue content unchanged.
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• Map relevant files that are too be used as reference from all repos mentioned
• import existing @GoodDollar packages
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Plan specification required sections:

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