Add Go examples to the learn pages - #3125

🤖 Automated message from the Stellar Triage Bot.

Refs #1770

Working this because @ElliotFriend approved the Go and Java splits in #1770 and asked me to keep building the stack. This is Go C: Go tabs on the 8 learn/ pages. Base: #3124 (docs-agent/1770-go-b). Go D and Java A to D follow.

What changed

• A Go tab next to every Stellar SDK example on these 8 pages under learn/fundamentals/:
  • stellar-data-structures/assets: tabs now in the order JavaScript, Python, Go, Java (Java moved after Python).
  • stellar-data-structures/events: the Go listener asks RPC for xdrFormat: "json", because the Go SDK has no scValToNative.
  • data-format/xdr: Go for the Uint64 primitive, the ScAddress union switch and ScAddress.String(). The Python Uint64 block moved into a code group with Go.
  • fees-resource-limits-metering: Go fee bump.
  • liquidity-on-stellar-sdex-liquidity-pools: all 6 code groups. Amounts stay in stroops (big.Rat, big.Int), and prices go through price.Parse.
  • contract-development/storage/state-archival: the same Go code as the reviewed archival guides in Add Go examples to the archival, conventions, rpc, conversions and events guides #3124.
  • contract-development/contract-interactions/transaction-simulation: all 3 examples.
  • contract-development/contract-interactions/stellar-transaction: a Go tab in <Tabs>, between Python and Java.
• Every transaction bids the capped fee-stats p90, like the other tabs.
• The Go SDK has no prepareTransaction and no auth-entry signer. Where a page needs one, the Go tab defines a small helper and says so in a comment.
• Prose changed only where it named JavaScript and Python alone, or where it named a JavaScript or Python helper with no Go match (xdr, state-archival).

Why this matters

Go readers had no example on these 8 pages. @ElliotFriend chose all four languages on every page in #1770.

Sweep

Not a claim fix, so no sweep. I checked the prose next to each new tab for text that named only JavaScript or Python, and updated it.

Verified

• Every Go symbol, field and type against go-stellar-sdk v0.9.0, the newest release (2026-11-12). The pages pin no Go SDK version.
  • txnbuild: transaction.go (NewTransaction, NewFeeBumpTransaction, FeeBumpTransactionParams; BaseFee() returns the bid without the resource fee, L220, L829), asset.go, change_trust.go, change_trust_asset.go, liquidity_pool_{deposit,withdraw,id,parameters}.go, payment.go.
  • clients/horizonclient: client.go (FeeStats, AccountDetail, LiquidityPoolDetail, Operations, SubmitTransaction, SubmitFeeBumpTransaction), main.go, liquidity_pool_request.go.
  • protocols/horizon: Balance, LiquidityPool, LiquidityPoolReserve, FeeDistribution.P90 (int64). operations/main.go unmarshals a deposit as the value type LiquidityPoolDeposit (L629-634).
  • clients/rpcclient/main.go: PollTransaction polls until its context ends (L242-294), so the Go tab sets a 30-second deadline and reports "status unknown" when it passes.
  • protocols/rpc: get_events.go (a cursor and a start ledger cannot both be set, L168-174), cursor.go (ParseCursor), format.go (FormatJSON), simulate_transaction.go, send_transaction.go, get_transaction.go.
  • xdr: xdr_generated.go (ScAddress arms, SorobanCredentialsTypeSorobanCredentialsAddressV2, HashIdPreimageSorobanAuthorizationWithAddress, Uint64), scval.go (ScAddress.String), asset.go (Asset.ContractID), main.go (MarshalBase64).
  • price/main.go (Parse), amount/main.go (ParseInt64, StringFromInt64), keypair/main.go (MustParseFull, MustRandom), strkey/main.go (MustEncode).
• Testnet runs Protocol 30 (Horizon testnet ledger 5705894). So the Go authorizeEntry on transaction-simulation signs both legacy and V2 address credentials, like the JavaScript and Python tabs there. V2 signs the ENVELOPE_TYPE_SOROBAN_AUTHORIZATION_WITH_ADDRESS preimage, which also holds the address, the same as py-stellar-base 17.0.1 stellar_sdk/auth.py build_authorization_preimage.
• pnpm check passes: prettier, mint validate, no broken links.

Not verified

• The Go code did not compile or run. go needs approval in this lane. A maintainer runs the Go blocks before merge, as @ElliotFriend said on Add Go examples to the transactions and basics guides #3123.
• CI may not run until the base is main (stacked PR).

Overlaps

• Stacked on Add Go examples to the archival, conventions, rpc, conversions and events guides #3124, then Add Go examples to the transactions and basics guides #3123, then Add Python examples to the guides and learn pages that lacked them #3115. Add Python examples to the guides and learn pages that lacked them #3115 edits 4 of these 8 pages (transaction-simulation, state-archival, fees-resource-limits-metering, events). Merge Add Python examples to the guides and learn pages that lacked them #3115, Add Go examples to the transactions and basics guides #3123 and Add Go examples to the archival, conventions, rpc, conversions and events guides #3124 first, then this PR.
• Older community PRs also edit some of these pages (Document externally managed contract executables #2775, 📊 Refresh Stellar Data Structures #2446, 💻 Convert low-res Soroban fee diagram to Mermaid #2407, 🧮 Manage data public info #1496). None adds Go.

Found in passing, not fixed here

#3119 collects defects in existing code, but it carries bot:hands-off, so I did not post there. A maintainer can move these to it.

1. liquidity-on-stellar-sdex-liquidity-pools.mdx (prose under the preamble): it says the two funded accounts are kp2 and kp3. The code names them kps[1] and kps[2] (kp1 and kp2).
2. Same page, JavaScript main(): it deposits from all three keypairs, the issuer kp0 too. Python, and now Go, deposit from kp1 and kp2 only.
3. stellar-transaction.mdx: the JavaScript and Java tabs call contract CBEOJUP5…KZW6, the Python tab CDMARRPK…5U73. The Go tab uses the JavaScript one.
4. Go A (Add Go examples to the transactions and basics guides #3123) signing-soroban-invocations.mdx: its Go authorizeEntry signs only legacy address credentials. Testnet runs Protocol 30, so simulation can return V2 entries that it skips. This PR's transaction-simulation Go tab handles both. I can port that to Add Go examples to the transactions and basics guides #3123 if you want it there.