chore(docs): Core concepts page in getting-started

[catmcgee]

A page in getting-started for devs to understand the bare minimum concepts of Aztec before they code. Closes #3398

Checklist:

Remove the checklist to signal you've completed it. Enable auto-merge if the PR is ready to merge.

• If the pull request requires a cryptography review (e.g. cryptographic algorithm implementations) I have added the 'crypto' tag.
• I have reviewed my diff in github, line by line and removed unexpected formatting changes, testing logs, or commented-out code.
• Every change is related to the PR description.
• I have linked this pull request to relevant issues (if any exist).

[AztecBot]

Benchmark results

Metrics with a significant change:

• note_trial_decrypting_time_in_ms (8): 5.16 (-45%)
• note_trial_decrypting_time_in_ms (32): 13.1 (-88%)

Detailed results

All benchmarks are run on txs on the Benchmarking contract on the repository. Each tx consists of a batch call to create_note and increment_balance, which guarantees that each tx has a private call, a nested private call, a public call, and a nested public call, as well as an emitted private note, an unencrypted log, and public storage read and write.

This benchmark source data is available in JSON format on S3 here.

Values are compared against data from master at commit c4e4745d and shown if the difference exceeds 1%.

L2 block published to L1

Each column represents the number of txs on an L2 block published to L1.

Metric	8 txs	32 txs	128 txs
l1_rollup_calldata_size_in_bytes	45,444	179,588	716,132
l1_rollup_calldata_gas	222,924	868,172	3,449,324
l1_rollup_execution_gas	842,011	3,595,280	22,204,693
l2_block_processing_time_in_ms	2,051 (+1%)	7,640	29,996
note_successful_decrypting_time_in_ms	302 (-2%)	903 (+1%)	3,273
note_trial_decrypting_time_in_ms	⚠️ 5.16 (-45%)	⚠️ 13.1 (-88%)	140 (-1%)
l2_block_building_time_in_ms	25,254	100,609	401,550
l2_block_rollup_simulation_time_in_ms	17,698 (+1%)	70,509	280,547
l2_block_public_tx_process_time_in_ms	7,512	29,954	120,446

L2 chain processing

Each column represents the number of blocks on the L2 chain where each block has 16 txs.

Metric	5 blocks	10 blocks
node_history_sync_time_in_ms	22,094	42,631 (-1%)
note_history_successful_decrypting_time_in_ms	2,153 (+1%)	4,075 (-2%)
note_history_trial_decrypting_time_in_ms	126 (+1%)	156 (-1%)
node_database_size_in_bytes	1,630,952	1,100,208
pxe_database_size_in_bytes	29,748	59,307

Circuits stats

Stats on running time and I/O sizes collected for every circuit run across all benchmarks.

Circuit	circuit_simulation_time_in_ms	circuit_input_size_in_bytes	circuit_output_size_in_bytes
private-kernel-init	399	43,077	20,441
private-kernel-ordering	126	25,833	9,689
base-rollup	3,177	659,500	873
root-rollup	91.9 (-1%)	4,072	1,097
private-kernel-inner	825	64,484	20,441
public-kernel-private-input	417	25,203	20,441
public-kernel-non-first-iteration	411	25,245	20,441
merge-rollup	10.8	2,592	873

Miscellaneous

Transaction sizes based on how many contracts are deployed in the tx.

Metric	0 deployed contracts	1 deployed contracts
tx_size_in_bytes	10,323	29,083

[critesjosh]

Overall this is a great addition! Just a few minor suggestions.

[critesjosh]

Should we a link to this page for further reading?

[critesjosh]

Should we add a link to this page for further reading?

[critesjosh]

Should we add a link to this page? https://docs.aztec.network/concepts/foundation/accounts/main

[critesjosh]

Suggested change

	Aztec smart contracts are written in a framework on top of Noir, the zero-knowledge domain-specific language developed specifically for Aztec. It is similar to Rust. Outside of Aztec, Noir is used for writing circuits that can be verified in Solidity.
	Aztec smart contracts are written in a framework on top of Noir, the zero-knowledge domain-specific language developed specifically for Aztec. It's syntax is similar to Rust. Outside of Aztec, Noir is used for writing circuits that can be verified in Solidity.

[signorecello]

Great work!