feat: improve semantic search marimo notebook

[jhamon]

Summary

Follow-up improvements to the semantic search marimo notebook merged in #581.

Changes

Multilingual support

• Switch embedding model to multilingual-e5-large for cross-lingual retrieval
• Embed both English and Spanish sentences from Tatoeba using filter_pairs + extract_sentences(lang)
• Add cross-lingual query examples and a language filtering section using Pinecone metadata filters

Interactivity

• Interactive query input with mo.ui.text and mo.ui.radio language selector
• Interactive API key input: reads PINECONE_API_KEY from env/.env with a mo.ui.text(kind="password") fallback for molab users; uses mo.callout admonitions for each state

Display

• Search results rendered as mo.ui.table with a lang column showing which language each hit came from
• Progress bar via mo.status.progress_bar (replacing tqdm)

Correctness / hygiene

• Pin datasets==3.5.1 — datasets>=4 dropped support for custom loading scripts used by Helsinki-NLP/tatoeba
• Use keyword argument names in all Pinecone API calls
• Remove unused numpy and tqdm dependencies
• Remove notebook-specific deps from root pyproject.toml (they belong in the notebook's # /// script inline metadata)

Test Plan

• Notebook runs end-to-end in sandbox mode (uvx marimo edit --sandbox) with a valid PINECONE_API_KEY
• Password input appears when env var is unset; success callout appears when set
• Cross-lingual queries return results in both English and Spanish
• Language filter correctly scopes results to en or es
• Interactive query input updates results on change

🤖 Generated with Claude Code

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Note

Low Risk
Low risk documentation/notebook-only changes that adjust dependency pinning and interactive API key handling; no production code paths affected.

Overview
Improves the docs/semantic-search.py semantic search marimo notebook setup experience by pinning datasets==3.5.1 and replacing the env-only Pinecone key requirement with an interactive API key input (env/.env auto-detect + password field fallback with callouts).

Adds a guard (mo.stop) to halt execution until a key is provided and introduces a brief section clarifying client instantiation (including the example-only source_tag).

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