feat: add PPTESTCD glossary slide to PowerPoint export

[Shaakon35]

Issue

Closes #1325

Description

Adds a glossary slide as the second slide in the PowerPoint export (after the title slide, before content). The glossary is a two-column table (PPTESTCD | PPTEST) listing all PK parameter codes used in the presentation, looked up from metadata_nca_parameters.

Changes

• .collect_pptestcds() — collects all unique PPTESTCDs from statistics tables (column names), individual parameter tables (column names), and boxplot names across all dose groups.
• .build_glossary() — filters metadata_nca_parameters to matching codes and returns a sorted, deduplicated two-column data frame.
• .add_pptx_glossary_slides() — renders the glossary as a flextable on "Title Only" layout slides, splitting across multiple slides when exceeding 20 rows.
• create_pptx_dose_slides() — integrates the glossary after the title slide and adjusts slide index offsets so summary slide reordering remains correct.

Definition of Done

• Glossary slide inserted as the second slide in the PowerPoint export
• Table contains two columns: PPTESTCD and PPTEST
• Only PPTESTCDs actually used in the presentation are included
• Labels sourced from metadata_nca_parameters
• Long glossaries split across multiple slides if needed
• Existing slide ordering preserved after the glossary

How to test

1. Run NCA on a dataset, then export PowerPoint via Save > PPTX
2. Open the generated .pptx — slide 2 should be a "Glossary" table
3. Verify the table lists only the PPTESTCDs that appear in the rest of the deck
4. Test with a dataset that produces many parameters (>20) to verify multi-slide splitting

Contributor checklist

• Code passes lintr checks
• Code passes all unit tests
• New logic covered by unit tests
• New logic is documented
• App or package changes are reflected in NEWS
• Package version is incremented
• R script works with the new implementation (if applicable)
• Settings upload works with the new implementation (if applicable)
• If any .scss change was done, run data-raw/compile_css.R
• If a package dependency was added/changed, run data-raw/test_suggests_hidden.R

Notes to reviewer

• The glossary only includes PPTESTCDs that match entries in metadata_nca_parameters. Non-standard codes (e.g., column names like "Statistic", "USUBJID") that appear in table headers are silently excluded since they have no match in the metadata.
• The max_rows parameter (default 20) controls pagination. Adjustable if the template layout fits more or fewer rows.
• Slide index arithmetic in create_pptx_dose_slides was updated: lst_group_slide starts at 1 + n_glossary_slides and summary slides move to first_content_pos (= 2 + n_glossary_slides) instead of hardcoded 2."

[h5hoang]

glossary shows up as intended on slide 2 and properly lists only the PPTESTCDs that appear in the rest of the deck, but overflows out of bounds of the slide layout with more params :

as you noted in the reviewer notes, changing the max_rows from 20 to ~8 to should fit within the slide bounds and I think it might be worth considering moving the table up to fill up the whitespace between "Glossary" and the table. But I think it looks good so far ! :)

[Shaakon35]

glossary shows up as intended on slide 2 and properly lists only the PPTESTCDs that appear in the rest of the deck, but overflows out of bounds of the slide layout with more params :

Thanks for the feedback, I implemented the changes :)
@h5hoang

[h5hoang]

LGTM now!

just a comment:

• fontsize(size = 9) in add_pptx_sl_plottable and add_pptx_sl_table affects all existing slide types, not just the glossary, it looks fine so far from my testing cause it's just font size changes, but this is a change from main so might be worth putting in the PR description

[Shaakon35]

@KOBANAK or @daviesmeg Could you have a review please? :)

[KOBANAK]

I confirm it works as expected.