LCFS - Auto-populate volume of eligible renewable fuel previously retained (Line 7 of the report summary)


**Description:**
Implement a feature to auto-populate the volume of eligible renewable fuel previously retained from the prior compliance period for each fuel class (Gasoline, Diesel, Jet Fuel) in the compliance report. If no previous compliance report is available, provide a free text field option for user input, restricted to positive number values.

**Wireframe:**
[link](https://preview.uxpin.com/da68049c0af15edd7ce4e47e4bee431fed40c30d#/pages/178083833?mode=m)

**Purpose and benefit to user:**
To streamline the compliance reporting process by auto-populating previously retained fuel volumes, ensuring accuracy and reducing manual data entry. This aids in tracking and managing surplus renewable fuel for future compliance periods.

**Acceptance Criteria:**
- [ ] Given I am a BCeID user, When I view the compliance report, then cells G7, D7, and J7 auto-populate with the volume noted in the prior year’s Line 6 compliance report for each fuel class.
- [ ] Given I am a BCeID user, When there is no previous compliance report available, then I see free text fields in cells G7, D7, and J7 for user input, restricted to positive number values.

**Development Checklist:**

- [ ] Implement logic to fetch and auto-populate cells G7, D7, and J7 with data from the prior year’s Line 6 compliance report.
- [ ] Add free text fields for user input in cells G7, D7, and J7 if no previous compliance report is available, restricted to positive number values.
- [ ] Test the auto-populate functionality to ensure it correctly fetches and displays the prior year’s retained fuel volumes.
- [ ] Test the conditional visibility and input restrictions of the free text fields to ensure correct functionality.

**Notes:**
- Confirm the data retrieval process from the previous compliance report for accurate auto-population.
- Ensure the data validation rules for positive number values in the free text fields.

Start by tracing the compliance report implementation and the handling of Line 6 data from the prior compliance period. Confirm how fuel classes map to cells G7, D7, and J7, then verify that missing prior reports show positive-number inputs. Done means prior retained volumes auto-populate correctly and fallback fields enforce the stated validation.

Written by the indexing model from the issue text.