feat(gui): material database browser + UserTally editor

[dhanavanthesh]

Closes TODO.md lines 46, 102, 103.

• Implement UserTally options/definition in GUI
• Add a database of pre-defined materials with full definition
• Pressing add material presents a selection/search function

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Two config sections that required hand-written JSON now have full GUI editors.

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Materials

A database search button is added first in the button row opens a dialog over 59 pre-defined materials loaded via ojson (no QJsonDocument).

• Name filter: type "iron" gets Fe, FeO, Fe2O3, Fe3O4
• Element filter: type "Fe" gets every material containing an Fe atom
• Preview shows density + full composition table (Symbol, X, Ed, El, Es, Er, Rc) before accepting
• Accept then material auto-selected, density and composition pre-filled. Zero typing.
• Combo, density spinbox, color button disabled when list is empty
• Duplicate IDs shown as "Fe" and "Fe (2)"
• Tooltips corrected: "Add material from database" / "Add new material" / "Remove material" / "Rename material"

materials-screen-recording.mp4

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UserTally

// TODO !! at simulationoptionsview.cpp:74 replaced with a full UserTallyView widget.

Tally management

• Add, remove, rename, duplicate from toolbar
• Duplicate produces collision-safe id: _copy, _copy2, ...
• Event picker: IonStop, IonExit, Vacancy, Replacement, CascadeComplete, BoundaryCrossing
• Disables during simulation run, reloads on revert

Bin variable table

• 14 variables in a dropdown with name + description
• [~] - linspace dialog per row: enter min, max, N, live edge preview
• [×] - removes that variable
• Non-monotonic edges turn the cell red

Live summary

• "2D tally: x × E (100 × 50 = 5000 bins)"
• Amber at 10.000 bins, red at 200.000
• Memory shown as ~40.0 KB / ~2.30 MB
• Warning text at 500.000 bins

Coordinate system

• "Use lab frame" checkbox hides origin/z-axis/xz-vector fields when not needed

Templates

• 6 presets: Depth Profile, Angular Distribution, Energy Spectrum, Implantation Map, Vacancy Depth Profile, Lateral Spread
• Preview shows x : 0 to 100 (100 bins) per variable
• If no tallies exist, one is created automatically before the dialog opens
• Template JSON cached after first parse

user_tally-screen-recording.mp4

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Also fixed a latent issue in OptionsModel - setData(idx, QVariant()) was silently reaching ojson::parse("") on every array edit from the GUI. Replaced with notifyDataChanged() across all 11 call sites in materialsdefview and regionsview. Empty string guard added in parse_json::set_impl_. Container nodes marked non-editable in flags().

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New: materialdatabasedialog.h/.cpp, usertallyview.h/.cpp,
database-search.svg, materials_database.json, tally_templates.json

Modified: materialsdefview, simulationoptionsview, optionsmodel,
parse_json.cpp, opentrim.qrc, CMakeLists.txt, TODO.md

[gapost]

Thank you for your contribution and the effort you put into this PR!

Unfortunately, I'll be closing it for two reasons:

1. Duplicate work – A solid implementation of the materials database dialog was already proposed in PR feat: Add MaterialDatabaseDialog for selecting predefined materials #8, which is currently in progress. Duplicating this effort creates unnecessary review overhead and goes against open source best practices around coordination.

2. Scope – Bundling two large, independent features into a single PR makes it significantly harder to review, test, and merge cleanly.

Your work on the usertally editor is genuinely appreciated, and I don't want it to go to waste. Please submit it as a standalone PR and I'll be happy to review it properly.

Thanks for understanding, and I look forward to your next contribution!

[dhanavanthesh]

Thank you for the feedback. Opened the UserTally editor as a standalone PR #14 . @gapost ready for review when you get a chance